staging: brcm80211: Optimized wl_inform_single_bss function in brcmfmac driver

Earlier verion of wl_inform_single_bss function is using
'cfg80211_inform_bss_frame' API for sending bss info to cfg80211.
With this patch same will be done through a more optimal
'cfg80211_inform_bss' API.

Cc: devel@linuxdriverproject.org
Cc: linux-wireless@vger.kernel.org
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Brett Rudley <brudley@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>