staging: vt6656: set all cck rates to default.

mac80211 rate control decides which cck rates to use so all of
them should be set enabled at the appropriate bit rate.

This means vnt_get_cck_rate is no longer required.

Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Link: https://lore.kernel.org/r/dec847da-5bad-1920-f275-741f7f704fb3@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>