colibri-imx8qxp: rename all occurences to colibri-imx8x

The Toradex product is called colibri-imx8x consisting of SoM with
i.MX8QXP and i.MX8DX SoCs.

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Reviewed-by: Igor Opaniuk <igor.opaniuk@toradex.com>
diff --git a/board/toradex/colibri-imx8x/MAINTAINERS b/board/toradex/colibri-imx8x/MAINTAINERS
index f685358..de62f87 100644
--- a/board/toradex/colibri-imx8x/MAINTAINERS
+++ b/board/toradex/colibri-imx8x/MAINTAINERS
@@ -5,6 +5,6 @@
 F:	arch/arm/dts/fsl-imx8x-colibri.dts
 F:	arch/arm/dts/fsl-imx8x-colibri-u-boot.dtsi
 F:	board/toradex/colibri-imx8x/
-F:	configs/colibri-imx8qxp_defconfig
+F:	configs/colibri-imx8x_defconfig
 F:	doc/board/toradex/colibri-imx8x.rst
 F:	include/configs/colibri-imx8x.h