fs: autofs: fix memory leak in autofs_fill_super()

In the Linux kernel, the following vulnerability has been resolved: fs: autofs: fix memory leak in autofs_fill_super() In autofs_fill_super(), we create a new inode using autofs_new_ino(), however, if we fail to create root_inode, (that is, root_inode failure path), we return -ENOMEM without freeing the new inode(ino) that we created causing a memory leak. Fix this by adding autofs_free_ino() to free the inode we created in root_inode failure path before returning ENOMEM.