makepkg: add fallback for when MAN_DIRS is unset

This prevents makepkg compressing every file when MAN_DIRS is not
supplied in makepkg.conf

Signed-off-by: Allan McRae <allan@archlinux.org>
Signed-off-by: Dan McGee <dan@archlinux.org>

scripts/makepkg.sh.in

@@ -719,6 +719,10 @@ tidy_install() {
 	if [ "$(check_option zipman)" = "y" ]; then
 		msg2 "$(gettext "Compressing man and info pages...")"
 		local manpage ext file link hardlinks hl
+		if [ -z "${MAN_DIRS[*]}" ]; then
+			# fall back to default value
+			MAN_DIRS=({usr{,/local}{,/share},opt/*}/{man,info})
+		fi
 		find ${MAN_DIRS[@]} -type f 2>/dev/null |
 		while read manpage ; do
 			# check file still exists (potentially compressed with hard link)