ath9k: hif_usb: simplify if-if to if-else

Use if and else instead of if(A) and if (!A).

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20220424094441.104937-1-wanjiabing@vivo.com