ARM: dts: imx6qdl: Fix memory node duplication

Boards based on imx6qdl have duplicate memory nodes:
- One coming from the board device tree file: memory@
- One coming from the imx6qdl.dtsi file.

Fix the duplication by removing the memory node from
the imx6qdl.dtsi file and by adding 'device_type = "memory";'
in the board Device Tree.

Converted using the following command:
perl -p0777i -e 's/memory\@10000000 \{\n/memory\@10000000 \{\n\t\tdevice_type = \"memory\";\n/m' `find ./arch/arm/boot/dts -name "imx6*"``

Reported-by: Rob Herring <robh@kernel.org>
Signed-off-by: Marco Franchi <marco.franchi@nxp.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
diff --git a/arch/arm/boot/dts/imx6qdl-udoo.dtsi b/arch/arm/boot/dts/imx6qdl-udoo.dtsi
index 40d1b0d..776bfc7 100644
--- a/arch/arm/boot/dts/imx6qdl-udoo.dtsi
+++ b/arch/arm/boot/dts/imx6qdl-udoo.dtsi
@@ -32,6 +32,7 @@
 	};
 
 	memory@10000000 {
+		device_type = "memory";
 		reg = <0x10000000 0x40000000>;
 	};