Wire up new syscalls

* linux/dummy.h (sys_bpf, sys_execveat, sys_getrandom,
sys_kexec_file_load, sys_memfd_create, sys_seccomp): New stub aliases.
* linux/32/syscallent.h (seccomp, getrandom, memfd_create, bpf,
execveat): New entries.
* linux/64/syscallent.h: Likewise.
* linux/arm/syscallent.h: Likewise.
* linux/hppa/syscallent.h: Likewise.
* linux/i386/syscallent.h: Likewise.
* linux/microblaze/syscallent.h: Likewise.
* linux/mips/syscallent-n32.h: Likewise.
* linux/mips/syscallent-n64.h: Likewise.
* linux/mips/syscallent-o32.h: Likewise.
* linux/powerpc/syscallent.h: Likewise.
* linux/sparc/syscallent.h: Likewise.
* linux/ia64/syscallent.h (getrandom, memfd_create, bpf, execveat):
New entries.
* linux/m68k/syscallent.h: Likewise.
* linux/s390/syscallent.h: (seccomp, getrandom, memfd_create, bpf,
s390_pci_mmio_write, s390_pci_mmio_read, execveat): New entries.
* linux/s390x/syscallent.h: Likewise.
* linux/x86_64/syscallent.h (seccomp, getrandom, memfd_create,
kexec_file_load, bpf, execveat): New entries.
* linux/x32/syscallent.h: Likewise.
* linux/xtensa/syscallent.h (seccomp, getrandom, memfd_create):
New entries.
diff --git a/linux/dummy.h b/linux/dummy.h
index 30ee94c..576fede 100644
--- a/linux/dummy.h
+++ b/linux/dummy.h
@@ -32,17 +32,23 @@
 #endif
 
 /* still unfinished */
+#define	sys_bpf			printargs
+#define	sys_execveat		printargs
+#define	sys_getrandom		printargs
 #define	sys_ioperm		printargs
 #define	sys_iopl		printargs
 #define	sys_kcmp		printargs
+#define	sys_kexec_file_load	printargs
 #define	sys_lookup_dcookie	printargs
+#define	sys_memfd_create	printargs
 #define	sys_name_to_handle_at	printargs
 #define	sys_open_by_handle_at	printargs
 #define	sys_sched_getattr	printargs
 #define	sys_sched_setattr	printargs
+#define	sys_seccomp		printargs
 #define	sys_sysfs		printargs
-#define	sys_vm86old		printargs
 #define	sys_vm86		printargs
+#define	sys_vm86old		printargs
 
 /* machine-specific */
 #if !(defined I386 || defined X86_64 || defined X32)