Verify that inode size is sane when loading inode with data stored in
ICB. Otherwise we may get confused later when working with the inode and
inode size is too big.

CC: stable@vger.kernel.org
Reported-by: NCarl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: NJan Kara <jack@suse.cz>