msm: msm-krait-l2-accessors: Add RTB logging

Accesses to indirect CP15 registers are important system events that
are worth recording in the RTB logs. The logs may aid in debugging
issues seen following operations that use these APIs, like CPU clock
source selection changes.

Change-Id: Ibc98ba2d58ab809a9e22bab4b6fcadd1e00e5f70
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>