Kprobes on select architectures no longer EXPERIMENTAL

Based on usage and testing over the past couple of years, kprobes on
i386, ia64, powerpc and x86_64 is no longer EXPERIMENTAL.

This is a follow-up to Robert P.J. Day's patch making "Instrumentation
support" non-EXPERIMENTAL:

	http://marc.info/?l=linux-kernel&m=118396955423812&w=2



Arch maintainers for sparc64, avr32 and s390 need to take a similar call.

Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>