x86: Constify a few items

x86: Constify a few items

This in particular re-does the compiler warning fix 9faec5b
("perf/x86: Fix P6 driver section warning"), tightening the
section attributes rather than relaxing them.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Shaun Ruffell <sruffell@digium.com>
Cc: yangyongqiang <yangyongqiang01@baidu.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/513DB84502000078000C4880@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>