msm: kgsl: Fix pagefault handler and stall on fault

On some platforms, certain IOMMU hardware state
might be cleared before reaching client fault handlers,
making it difficult for client fault handlers to do much
useful processing. Instead, use the pagefault information
passed in by the IOMMU fault handler. Eliminate the race
condition where the kworker thread could initiate recovery/GPU
reset before the pagefault handler has had a chance to run.
Fix the stall on fault path.

Change-Id: I2414a02ca55357a7eab863a973638b37846b82a1
Signed-off-by: Sushmita Susheelendra <ssusheel@codeaurora.org>