fuse: write inode in fuse_release()

In the Linux kernel, the following vulnerability has been resolved:

fuse: write inode in fuse_release()

A race between write(2) and close(2) allows pages to be dirtied after

fuse_flush -> write_inode_now(). If these pages are not flushed from

fuse_release(), then there might not be a writable open file later. So any

remaining dirty pages must be written back before the file is released.

This is a partial revert of the blamed commit.