hostap TX fix in 5.x [Fwd: Re: wi hostap speed]

I spent a few hours tinkering (tampering?) with this driver, and have not
exactly a fix, but a clear indication of what the problem is.

Verified (using the quick hack below): download speed geoes up from 170
kbytes/sec to 470 kbytes/sec, which is what I'd expect on an 11Mbps network.

If anyone's interested, here it is:

The Intersil manual on page 4-28 says that transmit packets need to have their
TxRate field filled in with 10,20,55 or 110, depending on the transmission speed.

The 4.X driver sets the field tx_frame.wi_tx_rate in function
wihap_check_tx(), called from wi_start().

The 5.X driver calls this field frmhdr.wi_tx_rate, but leaves it zero.
If you want to run at 11MBps, add a line
                  frmhdr.wi_tx_rate = 110;
in wi_start(), just before the call to wi_write_bap().

(Obviously, this is just a cheesy hack.  The real code would have to find the
actual tx rate.  I just want to point out where the problem lies).