[klibc] Move -nostdinc -iwithprefix include to the CPP options

-nostdinc -iwithprefix include are CPP options, treat them as such.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/scripts/Kbuild.klibc b/scripts/Kbuild.klibc
index b4c4ee5..227b9bd 100644
--- a/scripts/Kbuild.klibc
+++ b/scripts/Kbuild.klibc
@@ -66,8 +66,7 @@
 # Defines used when compiling early userspace (klibc programs)
 # ---------------------------------------------------------------------------
 
-KLIBCREQFLAGS     := $(call cc-option, -fno-stack-protector, ) \
-		     -nostdinc -iwithprefix include
+KLIBCREQFLAGS     := $(call cc-option, -fno-stack-protector, )
 KLIBCARCHREQFLAGS :=
 KLIBCOPTFLAGS     :=
 KLIBCWARNFLAGS    := -W -Wall -Wno-sign-compare -Wno-unused-parameter
@@ -97,7 +96,8 @@
 KLIBCOBJDUMP	 := $(OBJDUMP)
 
 # klibc include paths
-KLIBCCPPFLAGS    := -I$(KLIBCINC)/arch/$(KLIBCARCHDIR)	\
+KLIBCCPPFLAGS    := -nostdinc -iwithprefix include \
+		    -I$(KLIBCINC)/arch/$(KLIBCARCHDIR)	\
                     -I$(KLIBCINC)/bits$(KLIBCBITSIZE)	\
 		    -I$(KLIBCOBJ)/../include		\
                     -I$(KLIBCINC)