ARM: dts: imx6ul-pico-hobbit: Do not hardcode the memory size

There are two variants of imx6ul-pico boards: one with 256MB and
another one with 512MB of RAM.

Do not hardcode the memory size in the device tree and let the
bootloader fill the correct value instead.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6ul-pico-hobbit.dts

@@ -51,8 +51,9 @@ / {
 	model = "Technexion Pico i.MX6UL Board";
 	compatible = "technexion,imx6ul-pico-hobbit", "fsl,imx6ul";
 
+	/* Will be filled by the bootloader */
 	memory@80000000 {
-		reg = <0x80000000 0x10000000>;
+		reg = <0x80000000 0>;
 	};
 
 	chosen {