wlcore: enable sleep during AP mode operation

Enable ELP authorization in AP mode and enable the use
of the wakeup bit in the ELP register.

Introduce AP role sleep configuration which is disabled
by default. When configured, it allows the AP to sleep
when ELP is authorized for it.

Signed-off-by: Kobi Leibovitch <kobi.lev100@gmail.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>