msm: kgsl: Force GPU fault on GPC error

GPC error is typically the result of mistake SW programming.
Force GPU fault for this interrupt so that we can debug it
with help of register dump.

Change-Id: I7e893fd44f26def752587ac511603ad52e82659d
Signed-off-by: Prakash Kamliya <pkamliya@codeaurora.org>