linux-imx

fuse: move page alloc

fuse_req_pages_alloc() is moved to file.c, since its internal use by the
device code will eventually be removed.

Rename to fuse_pages_alloc() to signify that it's not only usable for
fuse_req page array.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>