ath9k_htc: Fix ethtool reporting

Pass the correct module name and device interface so that
ethtool can display the proper values.

The firmware version will be fixed later on when the FW
can actually report a version. :)

Reported-by: Richard Farina <sidhayn@gmail.com>
Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Tested-by: Richard Farina <sidhayn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>