msm: kgsl: Don't deassert GBIF halt before GPU gdsc goes off

During adreno_stop, GBIF halt is asserted to halt any new
transaction from GPU before GPU power collapse but in current
code it was cleared immediately which can allow few GPU
transactions to go through before gdsc is turned-off and can
result in issues.

To avoid this situation don't deassert this halt before GPU
gdsc goes off. It will deassert automatically when gdsc goes
off but in case gdsc doesn't toggle as its a shared resource
deassert this during adreno_start to ensure wake-up doesn't
fail.

Change-Id: If0a892470d04a0f3a79a1ea882ee5bfd16ad24ed
Signed-off-by: Deepak Kumar <dkumar@codeaurora.org>