drm/sti: fix compositor debugfs creation

Fix typo and issue while creating the vid and mixer debugfs entries.

Signed-off-by: Vincent Abriou <vincent.abriou@st.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
diff --git a/drivers/gpu/drm/sti/sti_crtc.c b/drivers/gpu/drm/sti/sti_crtc.c
index bc1b186..e992bed 100644
--- a/drivers/gpu/drm/sti/sti_crtc.c
+++ b/drivers/gpu/drm/sti/sti_crtc.c
@@ -338,7 +338,7 @@
 	struct sti_compositor *compo = dev_get_drvdata(mixer->dev);
 
 	if (drm_crtc_index(crtc) == 0)
-		return sti_compositor_debufs_init(compo, crtc->dev->primary);
+		return sti_compositor_debugfs_init(compo, crtc->dev->primary);
 
 	return 0;
 }