ARM: 8798/1: remove unnecessary KBUILD_SRC ifeq conditional

You can always prefix machine/plat header search paths with
$(srctree)/ because $(srctree) is '.' for in-tree building.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

arch/arm/Makefile

@@ -264,13 +264,9 @@ platdirs := $(patsubst %,arch/arm/plat-%/,$(sort $(plat-y)))
 
 ifneq ($(CONFIG_ARCH_MULTIPLATFORM),y)
 ifneq ($(CONFIG_ARM_SINGLE_ARMV7M),y)
-ifeq ($(KBUILD_SRC),)
-KBUILD_CPPFLAGS += $(patsubst %,-I%include,$(machdirs) $(platdirs))
-else
 KBUILD_CPPFLAGS += $(patsubst %,-I$(srctree)/%include,$(machdirs) $(platdirs))
 endif
 endif
-endif
 
 export	TEXT_OFFSET GZFLAGS MMUEXT