(split) Use logical rather than bitwise OR in if() expression.
(split) Undo r195846 for now - allow raw frame transmit in monitor mode.

The original commit was supposed to stop the ability to do raw frame
injection in monitor mode to arbitrary channels (whether supported
by regulatory or not) however it doesn't seem to have been followed
by any useful way of doing it.

Apparently AHDEMO is supposed to be that way, but it seems to require
too much fiddly things (disable scanning, set a garbage SSID, etc)
for it to actually be useful for spoofing things.

So for now let's just disable it and instead look to filter transmit
in the output path if the channel isn't allowed by regulatory.
That way monitor RX works fine but TX will be blocked.

I don't plan on MFC'ing this to -10 until the regulatory enforcement
bits are written.
(split) After much toying around with this AMRR initial rate stuff,
I've decided that for 11n rates it's best to start (very) low and work
our way up.

So, from now on, the initial rate for AMRR 11n is MCS4.
It doesn't try MCS12 or MCS20 - at low signal strengths those don't
work very well at all.

AMRR will step the rate control up over time if things work out better.

Tested:

* Intel 5100
* Intel 5300 (using local diffs to test out 3x3 stream support)
(split) Mechanically convert to if_inc_counter().
(split) Merge branch 'CURRENT' (commit '805bdee0')
(split) Merge branch (commit '0789e26a')
(split) Merge branch 'CURRENT'

Conflicts:
	sys/net80211/ieee80211_output.c