autotools.mk: always pass -I m4, some package don't seem to set correct AMFLAGS (or any at all..)

SVN-Revision: 24574

include/autotools.mk

@@ -38,7 +38,7 @@ define autoreconf
 				$(AM_TOOL_PATHS) $(STAGING_DIR_HOST)/bin/autoreconf -v -f -i -s \
 					-B $(STAGING_DIR_HOST)/share/aclocal \
 					$(patsubst %,-B %,$(5)) \
-					$(patsubst %,-I %,$(4)) $(4) || true; \
+					$(patsubst %,-I %,$(4)) -I m4 $(4) || true; \
 			fi; \
 		) \
 	);