drm/imx: Remove last traces of struct imx_drm_crtc

When the definition of this struct was removed a forward declaration and an
unused struct member were still left around. Remove them because they serve
no purpose.

Fixes 44b460cfe554 ("drm: imx: remove struct imx_drm_crtc and imx_drm_crtc_helper_funcs")

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/gpu/drm/imx/imx-drm.h

@@ -10,7 +10,6 @@ struct drm_display_mode;
 struct drm_encoder;
 struct drm_framebuffer;
 struct drm_plane;
-struct imx_drm_crtc;
 struct platform_device;
 
 struct imx_crtc_state {

drivers/gpu/drm/imx/ipuv3-crtc.c

@@ -35,7 +35,6 @@
 struct ipu_crtc {
 	struct device		*dev;
 	struct drm_crtc		base;
-	struct imx_drm_crtc	*imx_crtc;
 
 	/* plane[0] is the full plane, plane[1] is the partial plane */
 	struct ipu_plane	*plane[2];