drm/exynos: Replace drm_framebuffer_{un/reference} with put,get functions

This patch unifies the naming of DRM functions for reference counting
of struct drm_framebuffer. The resulting code is more aligned with the
rest of the Linux kernel interfaces.
Signed-off-by: NThomas Zimmermann <tdz@users.sourceforge.net>
Signed-off-by: NInki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_drm_plane.c

@@ -132,7 +132,7 @@ static void exynos_drm_plane_reset(struct drm_plane *plane)
 	if (plane->state) {
 		exynos_state = to_exynos_plane_state(plane->state);
 		if (exynos_state->base.fb)
-			drm_framebuffer_unreference(exynos_state->base.fb);
+			drm_framebuffer_put(exynos_state->base.fb);
 		kfree(exynos_state);
 		plane->state = NULL;
 	}