bcmdhd: Enable Ad-Hoc (IBSS) mode

Enable Ad-Hoc (IBSS) mode for bcmdhd. We basically just need to set the
interface flag and avoid some P2P specific settings while scanning.

Also add the "station get" command for IBSS mode.

Change-Id: Ie6f0fa77b55d92a7c22cbda72bad200cbfaede04
Signed-off-by: Bruno Randolf <br1@einfach.org>
bcmdhd: workaround broken AC video queue in IBSS mode

The BCM4330 has problems with the WME video (AC_VI) queue in IBSS mode. If we
put packets into this AC, the symptoms are excessive RTS/CTS, most packets get
lost and the device get's stuck and no more packets can be sent, even on other
queues.

Since the AC queue selection happens in the firmware based on the DSCP priority
and we don't know a way to configure this in the driver the workaround is to
simply downgrade all packets which would go into AC_VI (priority 4 and 5, TOS
0x80 and 0xa0) to AC_BE (priority 3 "Excellent Effort"). It's not pretty but
makes the device usable.

Change-Id: I8911c0eef7f189fc55547f02279e7012bc267d47
Signed-off-by: Bruno Randolf <br1@einfach.org>
Slight updates
WTF is this doing here?