9p: Remove potentially bad parameter from function entry debug print.

Signed-off-by: NDuane Griffin <duaneg@dghda.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

fs/9p/vfs_inode.c

@@ -1022,7 +1022,8 @@ v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
 {
 	char *s = nd_get_link(nd);
 
-	P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name, s);
+	P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
+		IS_ERR(s) ? "<error>" : s);
 	if (!IS_ERR(s))
 		__putname(s);
 }