drm/ttm: flip the switch for driver allocated resources v2

Instead of both driver and TTM allocating memory finalize embedding the
ttm_resource object as base into the driver backends.

v2: fix typo in vmwgfx grid mgr and double init in amdgpu_vram_mgr.c

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210602100914.46246-10-christian.koenig@amd.com
diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c
index 17a4c5d..2a1229b 100644
--- a/drivers/gpu/drm/drm_gem_vram_helper.c
+++ b/drivers/gpu/drm/drm_gem_vram_helper.c
@@ -250,7 +250,8 @@ EXPORT_SYMBOL(drm_gem_vram_put);
 static u64 drm_gem_vram_pg_offset(struct drm_gem_vram_object *gbo)
 {
 	/* Keep TTM behavior for now, remove when drivers are audited */
-	if (WARN_ON_ONCE(!gbo->bo.resource->mm_node))
+	if (WARN_ON_ONCE(!gbo->bo.resource ||
+			 gbo->bo.resource->mem_type == TTM_PL_SYSTEM))
 		return 0;
 
 	return gbo->bo.resource->start;