MAINTAINERS: Update Rob Herring's email address

My Calxeda email address is going away.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Rob Herring <robh@kernel.org>

MAINTAINERS

@@ -783,7 +783,7 @@ F:	arch/arm/boot/dts/sama*.dts
 F:	arch/arm/boot/dts/sama*.dtsi
 
 ARM/CALXEDA HIGHBANK ARCHITECTURE
-M:	Rob Herring <rob.herring@calxeda.com>
+M:	Rob Herring <robh@kernel.org>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 F:	arch/arm/mach-highbank/
@@ -6256,7 +6256,7 @@ F:	drivers/i2c/busses/i2c-ocores.c
 
 OPEN FIRMWARE AND FLATTENED DEVICE TREE
 M:	Grant Likely <grant.likely@linaro.org>
-M:	Rob Herring <rob.herring@calxeda.com>
+M:	Rob Herring <robh+dt@kernel.org>
 L:	devicetree@vger.kernel.org
 W:	http://fdt.secretlab.ca
 T:	git git://git.secretlab.ca/git/linux-2.6.git
@@ -6268,7 +6268,7 @@ K:	of_get_property
 K:	of_match_table
 
 OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS
-M:	Rob Herring <rob.herring@calxeda.com>
+M:	Rob Herring <robh+dt@kernel.org>
 M:	Pawel Moll <pawel.moll@arm.com>
 M:	Mark Rutland <mark.rutland@arm.com>
 M:	Ian Campbell <ijc+devicetree@hellion.org.uk>