ARM: dts: msm: Ignore perf mon interrupt while going to XO shutdown

Add perf mon interrupt to the gic-map to be ignored so that the
system can go into XO shutdown when it is enabled.

Change-Id: I8abf5830aaac1e718ea022eea5266f5f48a7109f
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>