drm/ttm: fix access to uninitialized variable.

The resource is not allocated yet, so no chance that this will work.

Use the placement instead.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210607171152.15914-1-christian.koenig@amd.com

drivers/gpu/drm/ttm/ttm_bo.c

@@ -749,7 +749,7 @@ static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,
 	struct ww_acquire_ctx *ticket;
 	int ret;
 
-	man = ttm_manager_type(bdev, (*mem)->mem_type);
+	man = ttm_manager_type(bdev, place->mem_type);
 	ticket = dma_resv_locking_ctx(bo->base.resv);
 	do {
 		ret = ttm_resource_alloc(bo, place, mem);