MAINTAINERS: Extend dts entry for ARM64 mvebu files

Extend the mvebu entry to ARM64 device tree sources.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

MAINTAINERS

@@ -1279,6 +1279,7 @@ F:	arch/arm/mach-mvebu/
 F:	drivers/rtc/rtc-armada38x.c
 F:	arch/arm/boot/dts/armada*
 F:	arch/arm/boot/dts/kirkwood*
+F:	arch/arm64/boot/dts/marvell/armada*
 
 
 ARM/Marvell Berlin SoC support