ath9k_htc: Cleanup device identification

ath.ko is a common module shared between ath5k, ar9170usb, ath9k and ath9k_htc.
Adding driver specific data to the shared structure would impact all the
drivers. Handling USB device recognition for devices specific to ath9k_htc
can be handled within the driver itself.

Also, AR7010 refers to the processor used in both AR9280/AR9287 based
devices. Rename the device enumerations accordingly.

While at it, check properly for the bus type when choosing the EEPROM
base address for UB95.

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>