staging:r8188eu: update pkt->(data|tail|len) synchronously with...

staging:r8188eu: update pkt->(data|tail|len) synchronously with rx_(data|tail|len) in recv_frame structure

Original driver code uses rx_* members to store skb (pkt) fields
(instead of pkt->* members), pkt->* updated only after data
completely formed, not in process.

Update pkt->* after data buffer changed (with rx_*).

Signed-off-by: Ivan Safonov <insafonov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>