ARM: dts: msm: add PMU support for kona

Add a device node to enable the armv8 PMU counters. This allows
perf subsystem to measure the hardware/raw performance events, such
as cycles count, instructions count, L1 misses and so on.

Change-Id: Id0c28192f3bf781d58423c4a69b6118373a4b22b
Signed-off-by: Channagoud Kadabi <ckadabi@codeaurora.org>