linux-phytec-fsl

drm/radeon: clean up vram/gtt location handling

Add a per-asic MC (memory controller) mask which holds the
mak address mask the asic is capable of.  Use this when
calculating the vram and gtt locations rather using asic
specific functions or limiting everything to 32 bits.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>