imx-drm: imx-drm-core: fix error cleanup path for imx_drm_add_crtc()

imx_drm_add_crtc() was kfree'ing the imx_drm_crtc structure while
leaving it on the list of CRTCs.  Delete it from the list first.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/imx-drm/imx-drm-core.c

@@ -528,6 +528,7 @@ int imx_drm_add_crtc(struct drm_crtc *crtc,
 	return 0;
 
 err_register:
+	list_del(&imx_drm_crtc->list);
 	kfree(imx_drm_crtc);
 err_alloc:
 err_busy: