9p: Fix missing commas in mount options

Since commit c4fac9100456 ("9p: Implement show_options"), the mount
options of 9p filesystems are printed out with some missing commas
between the individual options:

p9-scratch on /mnt/scratch type 9p (rw,dirsync,loose,access=clienttrans=virtio)

Add them back.

Cc: stable@vger.kernel.org # 4.13+
Fixes: c4fac9100456 ("9p: Implement show_options")
Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

net/9p/client.c

@@ -82,7 +82,7 @@ int p9_show_client_options(struct seq_file *m, struct p9_client *clnt)
 {
 	if (clnt->msize != 8192)
 		seq_printf(m, ",msize=%u", clnt->msize);
-	seq_printf(m, "trans=%s", clnt->trans_mod->name);
+	seq_printf(m, ",trans=%s", clnt->trans_mod->name);
 
 	switch (clnt->proto_version) {
 	case p9_proto_legacy:

net/9p/trans_fd.c

@@ -724,12 +724,12 @@ static int p9_fd_show_options(struct seq_file *m, struct p9_client *clnt)
 {
 	if (clnt->trans_mod == &p9_tcp_trans) {
 		if (clnt->trans_opts.tcp.port != P9_PORT)
-			seq_printf(m, "port=%u", clnt->trans_opts.tcp.port);
+			seq_printf(m, ",port=%u", clnt->trans_opts.tcp.port);
 	} else if (clnt->trans_mod == &p9_fd_trans) {
 		if (clnt->trans_opts.fd.rfd != ~0)
-			seq_printf(m, "rfd=%u", clnt->trans_opts.fd.rfd);
+			seq_printf(m, ",rfd=%u", clnt->trans_opts.fd.rfd);
 		if (clnt->trans_opts.fd.wfd != ~0)
-			seq_printf(m, "wfd=%u", clnt->trans_opts.fd.wfd);
+			seq_printf(m, ",wfd=%u", clnt->trans_opts.fd.wfd);
 	}
 	return 0;
 }