fuse: honor RLIMIT_FSIZE in fuse_file_fallocate

commit 0cbade02 upstream.

fstests generic/228 reported this failure that fuse fallocate does not
honor what 'ulimit -f' has set.

This adds the necessary inode_newsize_ok() check.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Fixes: 05ba1f08 ("fuse: add FALLOCATE operation")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>