drm/amdgpu: Use allowed_domains for pinning dmabufs

drm/amdgpu: Use allowed_domains for pinning dmabufs

When determining the domains for pinning DMABufs, filter allowed_domains
and fail with a warning if VRAM is forbidden and GTT is not an allowed
domain.

Fixes: f5e7fabd1f5c ("drm/amdgpu: allow pinning DMA-bufs into VRAM if all importers can do P2P")
Suggested-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Felix Kuehling <felix.kuehling@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>