media: imx: add a driver for i.MX8MQ mipi csi rx phy and controller

Add a driver to support the i.MX8MQ MIPI CSI receiver. The hardware side
is based on
https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/media/platform/imx8/mxc-mipi-csi2_yav.c?h=imx_5.4.70_2.3.0

It's built as part of VIDEO_IMX7_CSI because that's documented to support
i.MX8M platforms. This driver adds i.MX8MQ support where currently only the
i.MX8MM platform has been supported.
Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/staging/media/imx/Makefile

@@ -16,3 +16,4 @@ obj-$(CONFIG_VIDEO_IMX_CSI) += imx6-mipi-csi2.o
 
 obj-$(CONFIG_VIDEO_IMX7_CSI) += imx7-media-csi.o
 obj-$(CONFIG_VIDEO_IMX7_CSI) += imx7-mipi-csis.o
+obj-$(CONFIG_VIDEO_IMX7_CSI) += imx8mq-mipi-csi2.o