msm: kgsl: Log external and transaction stalled iommu faults

Add check to log external and transaction stalled iommu
faults also instead of dumping fault type as unknown for
these faults.

Signed-off-by: Deepak Kumar <dkumar@codeaurora.org>
Change-Id: Id95082eba94d480335a3c5569d7ab34f6c500c71