msm: kgsl: change pm_qos_latency to pm-qos-latency

Use hyphen symbol instead of underscore for pm-qos-latency
property name. Hyphen should be used instead of underscore
in device tree property name.

Change-Id: I23f720159b4ecb3d81cbd13b570cee8fc633253a
Signed-off-by: Prakash Kamliya <pkamliya@codeaurora.org>