MAINTAINERS: Add maintainer for i.MX8qxp Display Controller

Add myself as the maintainer of i.MX8qxp Display Controller.

Signed-off-by: Liu Ying <[e-mail]>
Reviewed-by: Maxime Ripard <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

MAINTAINERS

···
 F:	drivers/gpu/drm/imx/ipuv3/
 F:	drivers/gpu/ipu-v3/
 
+DRM DRIVERS FOR FREESCALE IMX8 DISPLAY CONTROLLER
+M:	Liu Ying <[e-mail]>
+L:	[e-mail]
+S:	Maintained
+T:	git https://gitlab.freedesktop.org/drm/misc/kernel.git
+F:	Documentation/devicetree/bindings/display/imx/fsl,imx8qxp-dc*.yaml
+F:	drivers/gpu/drm/imx/dc/
+
 DRM DRIVERS FOR FREESCALE IMX BRIDGE
 M:	Liu Ying <[e-mail]>
 L:	[e-mail]