ath9k: P2P_CLIENT, send frames after 1ms AP/GO will aprear

AP/GO will aprear after NOA, wait 1ms to be sure AP
could receive/answer this frames.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>