msm: kgsl: Recovery policy change

Recovery algorithm is changed to
step 1: retry the same commands that hung the GPU
step 2: if step 1 fails, nop just the IB that hung the GPU
	and retry
step 3: if step 2 fails, skip commands in current context
        till end of frame and retry
step 4: if step 3 fails mark context as bad and execute
        the remaining commands from good contexts.

Previously we used to return -EDEADLK when recovery succeeds,
this is the same error code if the context is not recoverable.
With new policy if recovery succeeds we return -EAGAIN so that
userspace treats recovered context differently from the ones
that are not recoverable. If recovery fails we mark the context
as bad and return -EDEADLK.

Change-Id: I9fa3c40801964186866b6002e62f19cf6aa41361
Signed-off-by: Tarun Karra <tkarra@codeaurora.org>