msm: kgsl: Use GMU cold boot sequence for hard reset

During GPU hang recovery, KGSL goes to STATE_RESET.
When starting GMU from STATE_RESET, use the cold boot
initialization sequence instead of the warm boot
sequence. This provides a completely clean starting point.

CRs-Fixed: 2062271
Change-Id: Ie9b628775e61e05fd2231e167657882581b681d1
Signed-off-by: Kyle Piefer <kpiefer@codeaurora.org>