imx-drm: imx-drm-core: remove imx_drm_connector and imx_drm_encoder code

imx-drm: imx-drm-core: remove imx_drm_connector and imx_drm_encoder code

The core imx_drm_connector and imx_drm_encoder code is no longer
required - the connectors and encoders are all using the component
support, so we can remove this.

Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>