wlcore: AP mode - send non-data packets with basic rates

This solves interoperability issues with peer that don't seem to "hear"
management packets transmitted in higher rates. Based on a previous
patch by Igal Chernobelsky.

Cc: Igal Chernobelsky <igalc@ti.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Luciano Coelho <luca@coelho.fi>