ARM: digicolor: add the machine directory to Makefile

Make the digicolor specific DT_MACHINE_START entry visible.

Fixes: df8d742e929 (ARM: initial support for Conexant Digicolor CX92755 SoC)
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm/Makefile

@@ -150,6 +150,7 @@ machine-$(CONFIG_ARCH_BERLIN)		+= berlin
 machine-$(CONFIG_ARCH_CLPS711X)		+= clps711x
 machine-$(CONFIG_ARCH_CNS3XXX)		+= cns3xxx
 machine-$(CONFIG_ARCH_DAVINCI)		+= davinci
+machine-$(CONFIG_ARCH_DIGICOLOR)	+= digicolor
 machine-$(CONFIG_ARCH_DOVE)		+= dove
 machine-$(CONFIG_ARCH_EBSA110)		+= ebsa110
 machine-$(CONFIG_ARCH_EFM32)		+= efm32