drm/amdkfd: Using new gtt sa in amdkfd

This patch change the calls throughout the amdkfd driver from the old kfd-->kgd
interface to the new kfd gtt sa inside amdkfd

v2: change the new call in sdma code that appeared because of the sdma feature

Signed-off-by: Oded Gabbay <oded.gabbay@amd.com>
Reviewed-by: Alexey Skidanov <Alexey.skidanov@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>