Documentation, EDAC: Update xgene binding for missing register bus

Update the APM X-Gene SoC EDAC documentation binding to reference the
missing register bus for the SoC EDAC.
Signed-off-by: Loc Ho <lho@apm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: devicetree@vger.kernel.org
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: mchehab@osg.samsung.com
Cc: patches@apm.com
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Link: http://lkml.kernel.org/r/1453495625-28006-2-git-send-email-lho@apm.comSigned-off-by: Borislav Petkov <bp@suse.de>

Documentation/devicetree/bindings/edac/apm-xgene-edac.txt

@@ -16,6 +16,10 @@ Required properties:
 - regmap-mcba		: Regmap of the MCB-A (memory bridge) resource.
 - regmap-mcbb		: Regmap of the MCB-B (memory bridge) resource.
 - regmap-efuse		: Regmap of the PMD efuse resource.
+- regmap-rb		: Regmap of the register bus resource. This property
+			  is optional only for compatibility. If the RB
+			  error conditions are not cleared, it will
+			  continuously generate interrupt.
 - reg			: First resource shall be the CPU bus (PCP) resource.
 - interrupts            : Interrupt-specifier for MCU, PMD, L3, or SoC error
 			  IRQ(s).
@@ -64,6 +68,11 @@ Example:
 		reg = <0x0 0x1054a000 0x0 0x20>;
 	};
 
+	rb: rb@7e000000 {
+		compatible = "apm,xgene-rb", "syscon";
+		reg = <0x0 0x7e000000 0x0 0x10>;
+	};
+
 	edac@78800000 {
 		compatible = "apm,xgene-edac";
 		#address-cells = <2>;
@@ -73,6 +82,7 @@ Example:
 		regmap-mcba = <&mcba>;
 		regmap-mcbb = <&mcbb>;
 		regmap-efuse = <&efuse>;
+		regmap-rb = <&rb>;
 		reg = <0x0 0x78800000 0x0 0x100>;
 		interrupts = <0x0 0x20 0x4>,
 			     <0x0 0x21 0x4>,