dt-bindings: perf: Add DT bindings for QCOM LLCC PMU driver

This patch adds the dt-bindings for the QCOM LLCC PMU driver
that can count misses for LLCC at a per-CPU level.

Change-Id: I33a6d0dfde620bf8023075aae3764c9077e17018
Signed-off-by: Rama Aparna Mallavarapu <aparnam@codeaurora.org>