atl1: fix vlan tag regression

commit dc5596d920b504d263c7ca38bd76326179b13dee upstream

Commit 401c0aabec4b97320f962a0161a846d230a6f7aa introduced a regression
in the atl1 driver by storing the VLAN tag in the wrong TX descriptor
field.

This patch causes the VLAN tag to be stored in its proper location.

Tested-by: Ramon Casellas <ramon.casellas@cttc.es>
Signed-off-by: Jay Cliburn <jacliburn@bellsouth.net>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>