perf: Mark LLCC PMU events as readable from any cpu

Currently, when trying to read from the LLCC PMU, the read will be ignored
by the perf framework if the intended core of the read is idle. However,
the LLCC PMU can be read regardless. Add a mask to LLCC PMU events
indicating they can be read from any CPU.

Change-Id: I841f96ffa9421961db995d55ae4e6266be77f5c0
Signed-off-by: Jonathan Avila <avilaj@codeaurora.org>