wg-quick: openbsd: fix alternate routing table syntax

route(8) has always used the `-T` option to specify the
routing table; there is no `rdomain` option.

Signed-off-by: Ankur Kothari <ankur@lipidity.com>

src/tools/wg-quick/openbsd.bash

@@ -293,7 +293,7 @@ add_route() {
 	fi
 
 	if [[ -n $TABLE && $TABLE != auto ]]; then
-		cmd route -q -n add "-$family" -rdomain "$TABLE" "$1" -iface "$ifaceroute"
+		cmd route -q -n -T "$TABLE" add "-$family" "$1" -iface "$ifaceroute"
 	elif [[ $1 == */0 ]]; then
 		if [[ $1 == *:* ]]; then
 			AUTO_ROUTE6=1