[PATCH] orinoco: optimize Tx exception handling in orinoco

When processing Tx exception, only read data until addr1.  Rename
hermes_tx_descriptor_802_11 to hermes_txexc_data since it's only used to
Tx exceptions.  Reuse existing hermes_tx_descriptor structure.  Remove
fields after addr1 - they are not read from the card.

Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>