ARM: bcm2835: add SDHCI node to DT

Add the SDHCI device node to the SoC DT file. Add a dummy fixed-clock
to satisfy the SDHCI driver's clock lookup; eventually this should be
replaced by a real clock implementation. Add board specific properties
to the Raspberry Pi board file.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
diff --git a/arch/arm/boot/dts/bcm2835.dtsi b/arch/arm/boot/dts/bcm2835.dtsi
index 8917550..1d7e4f5 100644
--- a/arch/arm/boot/dts/bcm2835.dtsi
+++ b/arch/arm/boot/dts/bcm2835.dtsi
@@ -63,5 +63,19 @@
 			interrupt-controller;
 			#interrupt-cells = <2>;
 		};
+
+		sdhci: sdhci {
+			compatible = "brcm,bcm2835-sdhci";
+			reg = <0x7e300000 0x100>;
+			interrupts = <2 30>;
+			clocks = <&clk_mmc>;
+			status = "disabled";
+		};
+	};
+
+	clk_mmc: clock {
+		compatible = "fixed-clock";
+		#clock-cells = <0>;
+		clock-frequency = <100000000>;
 	};
 };