Trivial tweaks to error messages

* strace.c (test_ptrace_setoptions_followfork): Use kill_save_errno
instead of kill.
(trace): Use perror_msg instead of perror.
* count.c (set_sortby): Use error_msg_and_die instead of fprintf.
* syscall.c (qualify): Likewise.
* util.c (ptrace_restart): Expand error message.
(umoven): Likewise.
(umovestr): Likewise.
(upeek): Use perror_msg instead of sprintf + perror.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
4 files changed