drm: Pass the real error code back during GEM bo initialisation

In particular, I found I was hitting the max-file limit in the VFS,
and the EFILE was being magically transformed into ENOMEM. Confusion
reigns.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/drm_gem.c

@@ -140,7 +140,7 @@ int drm_gem_object_init(struct drm_device *dev,
 	obj->dev = dev;
 	obj->filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
 	if (IS_ERR(obj->filp))
-		return -ENOMEM;
+		return PTR_ERR(obj->filp);
 
 	kref_init(&obj->refcount);
 	atomic_set(&obj->handle_count, 0);