drm/gem: add drm_gem_object_put helper

Spelling out _unlocked for each and every driver is a annoying.
Especially if we consider how many drivers, do not know (or need to)
about the horror stories involving struct_mutex.

Add helper, which will allow us to transition the drivers one by one,
dropping the suffix.

v2: add missing space after function name (Jani)
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org> (v1)
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-13-emil.l.velikov@gmail.com

include/drm/drm_gem.h

@@ -364,17 +364,19 @@ static inline void drm_gem_object_get(struct drm_gem_object *obj)
 }
 
 /**
- * drm_gem_object_put_unlocked - drop a GEM buffer object reference
+ * drm_gem_object_put - drop a GEM buffer object reference
  * @obj: GEM buffer object
  *
  * This releases a reference to @obj.
  */
 static inline void
-drm_gem_object_put_unlocked(struct drm_gem_object *obj)
+drm_gem_object_put(struct drm_gem_object *obj)
 {
 	kref_put(&obj->refcount, drm_gem_object_free);
 }
 
+#define drm_gem_object_put_unlocked drm_gem_object_put
+
 void drm_gem_object_put_locked(struct drm_gem_object *obj);
 
 int drm_gem_handle_create(struct drm_file *file_priv,