msm: kgsl: Implement new method to load GMU firmware

The new combined GMU firmware image contains load regions
for both the TCMs as well as cached instruction memory.
Implement the procedure to load firmware into the right
regions (ITCM/DTCM/cached instructions region) based on
the load region start address and size information.

Change-Id: Iff0474bd830583b4169563d8b1718ab6795df214
Signed-off-by: Carter Cooper <ccooper@codeaurora.org>