respect CFLAGS

--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -5,5 +5,5 @@ spacearyarya_SOURCES = extern.h \
                your.c your.h ranking.c ranking.h \
                boss.c boss.h

-CFLAGS = @X_CFLAGS@ @KXL_CFLAGS@
+AM_CFLAGS = @X_CFLAGS@ @KXL_CFLAGS@
 LIBS = @X_LIBS@ -lX11 @KXL_LIBS@ -lKXL