ptrace: Move ptrace_report_syscall into ptrace.h

Move ptrace_report_syscall from tracehook.h into ptrace.h where it
belongs.

Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-1-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>