powerpc/85xx: Add eSDHC support for MPC8536DS boards

This patch simply adds sdhci node to the device tree.

We specify clock-frequency manually, so that eSDHC will work without
upgrading U-Boot. Though, that'll only work for default setup (1500
MHz) on new board revisions. For non-default setups, it's recommended
to upgrade U-Boot, since it will fixup clock-frequency automatically.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

arch/powerpc/boot/dts/mpc8536ds.dts

@@ -250,6 +250,14 @@ usb@2b000 {
 			phy_type = "ulpi";
 		};
 
+		sdhci@2e000 {
+			compatible = "fsl,mpc8536-esdhc", "fsl,esdhc";
+			reg = <0x2e000 0x1000>;
+			interrupts = <72 0x2>;
+			interrupt-parent = <&mpic>;
+			clock-frequency = <250000000>;
+		};
+
 		serial0: serial@4500 {
 			cell-index = <0>;
 			device_type = "serial";

arch/powerpc/boot/dts/mpc8536ds_36b.dts

@@ -250,6 +250,14 @@ usb@2b000 {
 			phy_type = "ulpi";
 		};
 
+		sdhci@2e000 {
+			compatible = "fsl,mpc8536-esdhc", "fsl,esdhc";
+			reg = <0x2e000 0x1000>;
+			interrupts = <72 0x2>;
+			interrupt-parent = <&mpic>;
+			clock-frequency = <250000000>;
+		};
+
 		serial0: serial@4500 {
 			cell-index = <0>;
 			device_type = "serial";