9p: default 9p transport module fix

The default 9p transport module is not chosen unless an option parameter (any)
is passed to mount, which thus returns a ENOPROTOSUPPORT. This fix moves the
check out of parse_opts into p9_client_create.

Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

net/9p/client.c

@@ -117,9 +117,6 @@ static int parse_opts(char *opts, struct p9_client *clnt)
 		}
 	}
 
-	if (!clnt->trans_mod)
-		clnt->trans_mod = v9fs_get_default_trans();
-
 	kfree(options);
 	return ret;
 }
@@ -689,6 +686,9 @@ struct p9_client *p9_client_create(const char *dev_name, char *options)
 	if (err < 0)
 		goto error;
 
+	if (!clnt->trans_mod)
+		clnt->trans_mod = v9fs_get_default_trans();
+
 	if (clnt->trans_mod == NULL) {
 		err = -EPROTONOSUPPORT;
 		P9_DPRINTK(P9_DEBUG_ERROR,