staging: vt6655: mac80211 conversion: s_cbFillTxBufHead

Covert to handle mac80211 sk_buff data removing fragmentation processing
via s_vFillFragParameter and calls to vGenerateMACHeader and s_vSWencryption

fragmentation is now handled by mac80211.

There is still more todos with this function when legacy net device code
have been remove from driver.
Signed-off-by: NMalcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>