drivers/net/wireless/ath/ath5k: Change constant name

Elsewhere, the tqi_type field is compared to constants having a name
beginning with AR5K_TX_QUEUE, rather than AR5K_TX_QUEUE_ID.  I have thus
converted AR5K_TX_QUEUE_ID_CAB to AR5K_TX_QUEUE_CAB.  This does, however,
change the value, so perhaps something else was wanted.

Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>