wlcore: use all AP basic rates as default

Sometimes we get a BSS_CHANGED_BEACON_ENABLED event before the basic
rates have been properly set.  To avoid problems with the firmware not
expecting to receive frames at rates that are not set during
CMD_START_ROLE, we now start with all basic rates by default.

Signed-off-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>