msm: kgsl: Add support for gmu wrapper memory region

In some targets, SMMU memory region mapped in middle of GPU region.
Due to this overlapping, when we try to map full memory region of
GPU, request_mem_region will be failed. To avoid that issue, split
GPU memory region and program it in gmu_wrapper.

Change-Id: I735fde1b47161abe690a018c8642e4211a4c12a7
Signed-off-by: Pankaj Gupta <gpankaj@codeaurora.org>