Use <asm/unistd.h> instead of <sys/syscall.h>

There are no users of SYS_* macros provided by <sys/syscall.h>,
and definitions of __NR_* macros could be obtained directly
from <asm/unistd.h>.

* defs.h: Include <asm/unistd.h> instead of <sys/syscall.h>.
* test/seccomp.c: Likewise.
* test/threaded_execve.c: Likewise.
* test/x32_lseek.c: Likewise.
* test/x32_mmap.c: Likewise.
* tests/_newselect.c: Likewise.
* tests/access.c: Likewise.
* tests/acct.c: Likewise.
* tests/aio.c: Likewise.
* tests/alarm.c: Likewise.
* tests/attach-f-p.c: Likewise.
* tests/bpf.c: Likewise.
* tests/brk.c: Likewise.
* tests/chmod.c: Likewise.
* tests/chown.c: Likewise.
* tests/chown32.c: Likewise.
* tests/chroot.c: Likewise.
* tests/clock_adjtime.c: Likewise.
* tests/clock_nanosleep.c: Likewise.
* tests/clock_xettime.c: Likewise.
* tests/copy_file_range.c: Likewise.
* tests/creat.c: Likewise.
* tests/dup2.c: Likewise.
* tests/dup3.c: Likewise.
* tests/epoll_create.c: Likewise.
* tests/epoll_create1.c: Likewise.
* tests/epoll_ctl.c: Likewise.
* tests/epoll_pwait.c: Likewise.
* tests/epoll_wait.c: Likewise.
* tests/eventfd.c: Likewise.
* tests/execveat.c: Likewise.
* tests/faccessat.c: Likewise.
* tests/fchdir.c: Likewise.
* tests/fchmod.c: Likewise.
* tests/fchmodat.c: Likewise.
* tests/fchown.c: Likewise.
* tests/fchown32.c: Likewise.
* tests/fchownat.c: Likewise.
* tests/fcntl.c: Likewise.
* tests/fcntl64.c: Likewise.
* tests/fdatasync.c: Likewise.
* tests/flock.c: Likewise.
* tests/fstat.c: Likewise.
* tests/fstat64.c: Likewise.
* tests/fstatat64.c: Likewise.
* tests/fstatfs.c: Likewise.
* tests/fstatfs64.c: Likewise.
* tests/fsync.c: Likewise.
* tests/ftruncate.c: Likewise.
* tests/ftruncate64.c: Likewise.
* tests/futimesat.c: Likewise.
* tests/get_mempolicy.c: Likewise.
* tests/getcwd.c: Likewise.
* tests/getdents.c: Likewise.
* tests/getdents64.c: Likewise.
* tests/getegid.c: Likewise.
* tests/getegid32.c: Likewise.
* tests/geteuid.c: Likewise.
* tests/geteuid32.c: Likewise.
* tests/getgid.c: Likewise.
* tests/getgid32.c: Likewise.
* tests/getgroups.c: Likewise.
* tests/getgroups32.c: Likewise.
* tests/getpgrp.c: Likewise.
* tests/getrandom.c: Likewise.
* tests/getresgid.c: Likewise.
* tests/getresgid32.c: Likewise.
* tests/getresuid.c: Likewise.
* tests/getresuid32.c: Likewise.
* tests/getrlimit.c: Likewise.
* tests/getrusage.c: Likewise.
* tests/getuid.c: Likewise.
* tests/getuid32.c: Likewise.
* tests/getxxid.c: Likewise.
* tests/ioctl_uffdio.c: Likewise.
* tests/ioperm.c: Likewise.
* tests/iopl.c: Likewise.
* tests/ipc.c: Likewise.
* tests/kill.c: Likewise.
* tests/lchown.c: Likewise.
* tests/lchown32.c: Likewise.
* tests/libmmsg.c: Likewise.
* tests/libsocketcall.c: Likewise.
* tests/link.c: Likewise.
* tests/linkat.c: Likewise.
* tests/llseek.c: Likewise.
* tests/lseek.c: Likewise.
* tests/lstat.c: Likewise.
* tests/lstat64.c: Likewise.
* tests/mbind.c: Likewise.
* tests/membarrier.c: Likewise.
* tests/memfd_create.c: Likewise.
* tests/migrate_pages.c: Likewise.
* tests/mkdir.c: Likewise.
* tests/mkdirat.c: Likewise.
* tests/mknod.c: Likewise.
* tests/mknodat.c: Likewise.
* tests/mlock.c: Likewise.
* tests/mlock2.c: Likewise.
* tests/move_pages.c: Likewise.
* tests/newfstatat.c: Likewise.
* tests/nsyscalls.c: Likewise.
* tests/old_mmap.c: Likewise.
* tests/oldselect.c: Likewise.
* tests/open.c: Likewise.
* tests/openat.c: Likewise.
* tests/pause.c: Likewise.
* tests/poll.c: Likewise.
* tests/prctl-seccomp-filter-v.c: Likewise.
* tests/prctl-seccomp-strict.c: Likewise.
* tests/preadv2-pwritev2.c: Likewise.
* tests/prlimit64.c: Likewise.
* tests/pselect6.c: Likewise.
* tests/ptrace.c: Likewise.
* tests/readdir.c: Likewise.
* tests/readlink.c: Likewise.
* tests/readlinkat.c: Likewise.
* tests/reboot.c: Likewise.
* tests/remap_file_pages.c: Likewise.
* tests/rename.c: Likewise.
* tests/renameat.c: Likewise.
* tests/renameat2.c: Likewise.
* tests/rmdir.c: Likewise.
* tests/rt_sigpending.c: Likewise.
* tests/rt_sigprocmask.c: Likewise.
* tests/rt_sigsuspend.c: Likewise.
* tests/rt_sigtimedwait.c: Likewise.
* tests/rt_tgsigqueueinfo.c: Likewise.
* tests/sched_get_priority_mxx.c: Likewise.
* tests/sched_rr_get_interval.c: Likewise.
* tests/sched_xetaffinity.c: Likewise.
* tests/sched_xetattr.c: Likewise.
* tests/sched_xetparam.c: Likewise.
* tests/sched_xetscheduler.c: Likewise.
* tests/sched_yield.c: Likewise.
* tests/seccomp-filter-v.c: Likewise.
* tests/seccomp-filter.c: Likewise.
* tests/seccomp-strict.c: Likewise.
* tests/select.c: Likewise.
* tests/sendfile.c: Likewise.
* tests/sendfile64.c: Likewise.
* tests/set_mempolicy.c: Likewise.
* tests/setdomainname.c: Likewise.
* tests/setfsgid.c: Likewise.
* tests/setfsgid32.c: Likewise.
* tests/setfsuid.c: Likewise.
* tests/setfsuid32.c: Likewise.
* tests/setgid.c: Likewise.
* tests/setgid32.c: Likewise.
* tests/setgroups.c: Likewise.
* tests/setgroups32.c: Likewise.
* tests/sethostname.c: Likewise.
* tests/setregid.c: Likewise.
* tests/setregid32.c: Likewise.
* tests/setresgid.c: Likewise.
* tests/setresgid32.c: Likewise.
* tests/setresuid.c: Likewise.
* tests/setresuid32.c: Likewise.
* tests/setreuid.c: Likewise.
* tests/setreuid32.c: Likewise.
* tests/setrlimit.c: Likewise.
* tests/setuid.c: Likewise.
* tests/setuid32.c: Likewise.
* tests/signalfd4.c: Likewise.
* tests/socketcall.c: Likewise.
* tests/splice.c: Likewise.
* tests/stat.c: Likewise.
* tests/stat64.c: Likewise.
* tests/statfs.c: Likewise.
* tests/statfs64.c: Likewise.
* tests/swap.c: Likewise.
* tests/symlink.c: Likewise.
* tests/symlinkat.c: Likewise.
* tests/sync.c: Likewise.
* tests/sync_file_range.c: Likewise.
* tests/sync_file_range2.c: Likewise.
* tests/syslog.c: Likewise.
* tests/tee.c: Likewise.
* tests/time.c: Likewise.
* tests/timer_create.c: Likewise.
* tests/timer_xettime.c: Likewise.
* tests/timerfd_xettime.c: Likewise.
* tests/times-fail.c: Likewise.
* tests/times.c: Likewise.
* tests/truncate.c: Likewise.
* tests/truncate64.c: Likewise.
* tests/ugetrlimit.c: Likewise.
* tests/umount.c: Likewise.
* tests/umount2.c: Likewise.
* tests/uname.c: Likewise.
* tests/unix-pair-send-recv.c: Likewise.
* tests/unlink.c: Likewise.
* tests/unlinkat.c: Likewise.
* tests/userfaultfd.c: Likewise.
* tests/utimes.c: Likewise.
* tests/vhangup.c: Likewise.
* tests/vmsplice.c: Likewise.
* tests/waitid.c: Likewise.
* tests/waitpid.c: Likewise.
* tests/xet_robust_list.c: Likewise.
* tests/xetpgid.c: Likewise.
* tests/xetpriority.c: Likewise.
* tests/xettimeofday.c: Likewise.
diff --git a/tests/readlinkat.c b/tests/readlinkat.c
index 5ca9e72..4d3b516 100644
--- a/tests/readlinkat.c
+++ b/tests/readlinkat.c
@@ -27,7 +27,7 @@
  */
 
 #include "tests.h"
-#include <sys/syscall.h>
+#include <asm/unistd.h>
 
 #ifdef __NR_readlinkat