x86: x86 ptrace generic requests

This removes duplicated code by calling the generic ptrace_request and
compat_ptrace_request functions for the things they already handle.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>