xbps-src: be more conservative with signal handlers.

xbps-src/shutils/pkgtarget_funcs.sh.in

@@ -124,14 +124,14 @@ install_pkg()
 
 	# Always write metadata to package's destdir.
 	. $XBPS_SHUTILSDIR/metadata.sh
-	trap 'remove_pkgdestdir_sighandler ${pkgname}' 0 INT
+	trap 'remove_pkgdestdir_sighandler ${pkgname}' INT
 	xbps_write_metadata_pkg
 	if [ $? -ne 0 ]; then
 		msg_red "cannot write package metadata for '$pkgname'!\n"
-		trap '' 0 INT
+		trap - INT
 		return 1
 	fi
-	trap '' 0 INT
+	trap - INT
 
 	[ "$install_destdir_target" = "yes" ] && return 0