staging: rtl8723au: rtw_check_beacon_data23a(): Capability is already uptodate in cur_network

Beacon capability was already added to mlme_priv->cur_network before
calling this function, so no need to retrieve it from the IE array
again.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>