ext4: avoid bh leak in retry path of ext4_expand_extra_isize_ea()

commit dcb9917b upstream.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>