msm: kgsl: Check for mmu pagefault before recovery

Check whether there is a pagefault before running recovery.
If recovery runs before the bottom pagefault handler runs
then there could be a pending pagefault at end of recovery that
can stall the IOMMU. With the IOMMU stalled the GPU would only
read back zeroes even after recovery.

CRs-Fixed: 642562
Change-Id: I78fb225b2ee57e87ac6ebd1f2c9bca18aa81d942
Signed-off-by: Shubhraprakash Das <sadas@codeaurora.org>