ARM: dts: msm: define CPU affinity of affine cores for msm8994

As msm8994 has little cluster, setting the pm qos to affine
cores instead of the default irq affinity can significantly
improve the performance of IO workloads.

Change-Id: Ifc3656b48bffa01cdd143073b2862e47b42f737f
Signed-off-by: Maya Erez <merez@codeaurora.org>