media: imx: Rename imx7-mipi-csis.c to imx-mipi-csis.c

Rename the imx7-mipi-csis.c driver to remove the reference to i.MX7.

The driver is for an IP core found on i.MX7 and i.MX8 SoC so do not
specify a SoC version number in the driver name.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>

MAINTAINERS

@@ -11885,7 +11885,7 @@ T:	git git://linuxtv.org/media_tree.git
 F:	Documentation/admin-guide/media/imx7.rst
 F:	Documentation/devicetree/bindings/media/nxp,imx7-csi.yaml
 F:	Documentation/devicetree/bindings/media/nxp,imx7-mipi-csi2.yaml
-F:	drivers/media/platform/imx/imx7-mipi-csis.c
+F:	drivers/media/platform/imx/imx-mipi-csis.c
 F:	drivers/staging/media/imx/imx7-media-csi.c
 
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