ARM: shmobile: Add missing dts files to MAINTAINERS

Add some more patterns to the ARM/SHMOBILE ARM ARCHITECTURE
section of MAINTAINERS to complete the list of maintained dts files.

As of writing dts files covered are:
* arch/arm/boot/dts/gr-peach-audiocamerashield.dtsi
* arch/arm/boot/dts/iwg20d-q7-common.dtsi
* arch/arm/boot/dts/iwg20d-q7-dbcm-ca.dtsi
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

MAINTAINERS

@@ -2109,6 +2109,8 @@ Q:	http://patchwork.kernel.org/project/linux-renesas-soc/list/
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas.git next
 S:	Supported
 F:	arch/arm/boot/dts/emev2*
+F:	arch/arm/boot/dts/gr-peach*
+F:	arch/arm/boot/dts/iwg20d-q7*
 F:	arch/arm/boot/dts/r7s*
 F:	arch/arm/boot/dts/r8a*
 F:	arch/arm/boot/dts/r9a*