mwx(4), another new wi-fi driver, added to -current

Hot on the heels of
qwx(4)
[see earlier report], and soon after going -beta,
-current has gained another new wi-fi driver –
mwx(4).
Claudio Jeker (claudio@)
committed
the import:

CVSROOT:	/cvs
Module name:	src
Changes by:	claudio@cvs.openbsd.org	2024/02/21 03:48:10

Modified files:
	sys/dev/pci    : files.pci 
Added files:
	sys/dev/pci    : if_mwx.c if_mwxreg.h 

Log message:
Import mwx(4) a driver for Mediatek MT7921 and MT7922 802.11ax devices

This is work in progress. Scan works, RX of packets is more or less there
but TX does not work yet. The packets are passed to the chip but get stuck
or ignored there. It is easy to hang the device or the system since device
reset is not quite right (like many other bits).

Also this is only for MT7921 right now since I have no access to a MT7922
device.

Lots of pushing from deraadt@ to commit this now.

So, WIP and
MT7921-only
[at this stage], but very promising.