msm: kgsl: Read fault register on ringbuffer h/w fault

Read the CP_HW_FAULT register which gives more information
about the fault when ringbuffer h/w fault interrupt is
generated. Also, limit the printing of this interrupt to
prevent watchdog timeout.

Change-Id: I8eba72ab50553e72f733034c7fa0ea3ca69db343
CRs-Fixed: 613940
Signed-off-by: Shubhraprakash Das <sadas@codeaurora.org>