gpu: drm: sti_hqvdp: add missing of_node_put after calling of_parse_phandle

of_node_put needs to be called when the device node which is got
from of_parse_phandle has finished using.

Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1467684294-20111-5-git-send-email-peter.chen@nxp.com
diff --git a/drivers/gpu/drm/sti/sti_hqvdp.c b/drivers/gpu/drm/sti/sti_hqvdp.c
index 33d2f42..b032322 100644
--- a/drivers/gpu/drm/sti/sti_hqvdp.c
+++ b/drivers/gpu/drm/sti/sti_hqvdp.c
@@ -1363,6 +1363,7 @@
 	vtg_np = of_parse_phandle(pdev->dev.of_node, "st,vtg", 0);
 	if (vtg_np)
 		hqvdp->vtg = of_vtg_find(vtg_np);
+	of_node_put(vtg_np);
 
 	platform_set_drvdata(pdev, hqvdp);