drivers: llcc_perfmon: Add llcc_perfmon support

This is snapshot of the llcc_perfmon driver from msm-4.14
'commit c9961d61d6d8 ("drivers: soc: llcc_perfmon: Add llcc_perfmon
		support")'

This LLCC perfmon driver provides Sysfs interfaces for the clients to
monitor the events. Driver support for monitor events from LLCC sub blocks.
Also updated driver to handle opcode & cache alloc filters.

Change-Id: Ic711fdbc774d2da1938feff5c0d7888e5cf8495a
Signed-off-by: Sankaran Nampoothiri <snampoot@codeaurora.org>
Signed-off-by: Avinash Philip <avinashp@codeaurora.org>