ARM: uniphier: compile pll-base-ld20.c for PXs3

Fix the link error for the combination of
  CONFIG_ARCH_UNIPHIER_LD11=n
  CONFIG_ARCH_UNIPHIER_LD20=n
  CONFIG_ARCH_UNIPHIER_PXS3=y

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

arch/arm/mach-uniphier/clk/Makefile

@@ -27,3 +27,4 @@ endif
 
 obj-$(CONFIG_ARCH_UNIPHIER_LD11)	+= pll-base-ld20.o
 obj-$(CONFIG_ARCH_UNIPHIER_LD20)	+= pll-base-ld20.o
+obj-$(CONFIG_ARCH_UNIPHIER_PXS3)	+= pll-base-ld20.o