x86: unify fault_32|64.c by ifdef'd function bodies

It's about time to get on with unifying these files, elimination
of the ugly ifdefs can occur in the unified file.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>