fix make distcheck with newer automake


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@1443 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/Makefile.am b/Makefile.am
index b63b452..df2e57e 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -8,7 +8,7 @@
 		lackey \
 		none
 
-CFLAGS = $(WERROR) -DVG_LIBDIR="\"$(libdir)"\" \
+AM_CFLAGS = $(WERROR) -DVG_LIBDIR="\"$(libdir)"\" \
 		-Winline -Wall -Wshadow -O -fomit-frame-pointer @PREFERRED_STACK_BOUNDARY@ -g
 
 valdir = $(libdir)/valgrind
@@ -19,6 +19,8 @@
 
 BUILT_SOURCES = default.supp
 
+CLEANFILES = default.supp
+
 default.supp: $(SUPP_FILES)
 
 bzdist: dist