ARM: uniphier: remove empty Makefile

arch/arm/mach-uniphier/Makefile has been unused for a long time.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/Makefile

@@ -222,7 +222,6 @@ machine-$(CONFIG_ARCH_TANGO)		+= tango
 machine-$(CONFIG_ARCH_TEGRA)		+= tegra
 machine-$(CONFIG_ARCH_U300)		+= u300
 machine-$(CONFIG_ARCH_U8500)		+= ux500
-machine-$(CONFIG_ARCH_UNIPHIER)		+= uniphier
 machine-$(CONFIG_ARCH_VERSATILE)	+= versatile
 machine-$(CONFIG_ARCH_VEXPRESS)		+= vexpress
 machine-$(CONFIG_ARCH_VT8500)		+= vt8500