Makefile: do not create a symbolic link to arch/${ARCH}/include/asm

In-tree build:
  - Do not create a symbolic link
      from include/asm to arch/${ARCH}/include/asm
  - Add ${SRCTREE}/arch/arm/include into the header search path

Out-of-tree build:
  - Do not create a directory ${OBJTREE}/include2
  - Do not create a symbolic link
      from ${OBJTREE}/include2/asm to ${SRCTREE}/arch/${ARCH}/include/asm
  - Add ${SRCTREE}/arch/arm/include into the header search path

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/config.mk b/config.mk
index 91a8f24..3441387 100644
--- a/config.mk
+++ b/config.mk
@@ -257,10 +257,10 @@
 endif
 
 ifneq ($(OBJTREE),$(SRCTREE))
-CPPFLAGS += -I$(OBJTREE)/include2 -I$(OBJTREE)/include
+CPPFLAGS += -I$(OBJTREE)/include
 endif
 
-CPPFLAGS += -I$(TOPDIR)/include
+CPPFLAGS += -I$(TOPDIR)/include -I$(SRCTREE)/arch/$(ARCH)/include
 CPPFLAGS += -fno-builtin -ffreestanding -nostdinc	\
 	-isystem $(gccincdir) -pipe $(PLATFORM_CPPFLAGS)