ARM: mvebu: Update the SDHCI node on Armada 38x

The binding of the armada-380-sdhci has been extended with a new
register in order to be able to use the SDR50 and DDR50 mode. This
commit add the resource associated to this new register for the
Armada 38x.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

arch/arm/boot/dts/armada-38x.dtsi

@@ -548,7 +548,10 @@ flash@d0000 {
 
 			sdhci@d8000 {
 				compatible = "marvell,armada-380-sdhci";
-				reg = <0xd8000 0x1000>, <0xdc000 0x100>;
+				reg-names = "sdhci", "mbus", "conf-sdio3";
+				reg = <0xd8000 0x1000>,
+					<0xdc000 0x100>,
+					<0x18454 0x4>;
 				interrupts = <GIC_SPI 25 IRQ_TYPE_LEVEL_HIGH>;
 				clocks = <&gateclk 17>;
 				mrvl,clk-delay-cycles = <0x1F>;