avoid Wuninitialized false positive in gcc-12ish

Author: djmdjm

channels.c

@@ -369,7 +369,7 @@ channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
     int nonblock)
 {
 	struct ssh_channels *sc = ssh->chanctxt;
-	u_int i, found;
+	u_int i, found = 0;
 	Channel *c;
 	int r;