staging: ath6kl: Convert BDADDR_Present uses to TRUE/FALSE bugfix

The previous uses of BDADDR_Present set the initial value to
A_ERROR (-1) when not present and A_OK (0) when present.

A later test for (!BDADDR_Present) was therefore logically inverted.
Convert the values to TRUE/FALSE and the test is now logically correct.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Vipin Mehta <vipin.mehta@atheros.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>