Got rid of the rare failure caused by a directory-time mismatch.

testsuite/merge.test

@@ -40,7 +40,9 @@ cp -p "$from2dir"/sub1/uno "$from3dir"/sub1/dos "$from2dir"/sub1/tres "$chkdir"/
 cp -p "$from3dir"/sub2/subby "$chkdir"/sub2
 
 # Get rid of any directory-time differences
-$RSYNC -av --existing --include='*/' --exclude='*' "$from1dir/" "$from2dir/" "$from3dir/" "$chkdir/"
+touch "$from1dir" "$from2dir" "$from3dir" \
+    "$from2dir"/sub1 "$from3dir"/sub1 "$from3dir"/sub2 \
+    "$chkdir" "$chkdir"/sub1 "$chkdir"/sub2
 
 checkit "$RSYNC -aHvv \"$from1dir/\" \"$from2dir/\" \"$from3dir/\" \"$todir/\"" "$chkdir" "$todir"