drm/cirrus: Delete an unnecessary check before drm_gem_object_unreference_unlocked()

Author: Markus Elfring <elfring@users.sourceforge.net>

The drm_gem_object_unreference_unlocked() function tests whether
its argument is NULL and then returns immediately.
Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring 
Signed-off-by: Daniel Vetter 
Link: http://patchwork.freedesktop.org/patch/msgid/bebf88d8-cc28-657a-e96c-58447d8cf376@users.sourceforge.net
---
 drivers/gpu/drm/cirrus/cirrus_main.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
 
diff --git a/drivers/gpu/drm/cirrus/cirrus_main.c b/drivers/gpu/drm/cirrus/cirrus_main.c
index 32d32c5..80446e2 100644
--- a/drivers/gpu/drm/cirrus/cirrus_main.c
+++ b/drivers/gpu/drm/cirrus/cirrus_main.c
@@ -17,8 +17,8 @@
 static void cirrus_user_framebuffer_destroy(struct drm_framebuffer *fb)
 {
 	struct cirrus_framebuffer *cirrus_fb = to_cirrus_framebuffer(fb);
-	if (cirrus_fb->obj)
-		drm_gem_object_unreference_unlocked(cirrus_fb->obj);
+
+	drm_gem_object_unreference_unlocked(cirrus_fb->obj);
 	drm_framebuffer_cleanup(fb);
 	kfree(fb);
 }