brcmfmac: set WIPHY_FLAG_HAVE_AP_SME flag

brcmfmac: set WIPHY_FLAG_HAVE_AP_SME flag

brcmfmac is a FullMAC driver and it implements/uses cfg80211 interface
for stations management. At the same time it doesn't receive or pass up
management frames.

This flag indicates that authenticator doesn't have to subscribe to or
handle management frames. Some authenticators (e.g. hostapd) were
working with brcmfmac thanks to some extra assumptions. This commit
clears up the situation.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>