ath6kl: remove redundant check of status != 0

The check on status not being zero is redundant as previous code
paths that set status to an error value break out of the while
loop and hence status is never non-zero at the check. Remove
this redundant code.

Addresses-Coverity: ("Logically dead code")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>