drm/amdgpu: Wire up MMIO_REMAP placement and User-visible strings

drm/amdgpu: Wire up MMIO_REMAP placement and User-visible strings

Wire up the conversions and strings for the new MMIO_REMAP placement:

* amdgpu_mem_type_to_domain() maps AMDGPU_PL_MMIO_REMAP -> domain
* amdgpu_bo_placement_from_domain() accepts the new domain
* amdgpu_bo_mem_stats_placement() and amdgpu_bo_print_info() report it
* res cursor supports the new placement
* fdinfo prints "mmioremap" for the new placement

Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>