wlcore: send EAPOLs with basic rate policy

EAPOLs are sent at high rates as they are considered
data packets. Some APs like Motorola Symbol AP7131 and AP650
don't respond well to these rates and don't respond with
EAPOL 3/4 consistently. When sending EAPOL 2/4 at 54Mbps
we've seen approx 30% success rate in getting EAPOL 3/4 response
while using 11Mbps we got 100% success.
To increase the chances of successful 4-Way handshake with
such APs, send EAPOLs with basic rate policy in order to avoid
high rates.

Signed-off-by: Eyal Shapira <eyal@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>