add -DHAVE_BROKEN_REALPATH to CFLAGS on FreeBSD (previous patch touched only CXXFLAGS)

configure.in

@@ -925,6 +925,7 @@ case $SYSTEM_TYPE in
     ;;
   *freebsd*)
     echo "Adding fix for interrupted reads"
+    CFLAGS="$CFLAGS -DHAVE_BROKEN_REALPATH"
     CXXFLAGS="$CXXFLAGS -DMYSQLD_NET_RETRY_COUNT=1000000 -DHAVE_BROKEN_REALPATH"
     ;;
   *netbsd*)