De-orbit Allwinner A10/A20/A31 for 12.0

[Emmanuel Vadot]

 Hello arm@

 I don't like to send this email but ...

 I want to remove A10/A20/A31 support for FreeBSD 12, here is the
reason why :

 - I don't have time to maintain thoses SoC
 - For A10/A20 we currently don't boot on it since it requires new
clocks binding (handled by aw_ccung) and I have no time to do the
switch.
 - H3 (which is 32bits too) is way better in term of performance and
price, you can buy a "good" $10 board while getting an A20 will cost
you more for some reason.
 - My A31 board (BananapiM1) just died today after a long time of being
my arm32 reference board.
 - I don't want the code to stay like the old 32 bits rockchip or
amlogic code that can't even boot nowadays.

 If someone want to step up and convert A10/A20 to ccung I'll be
glad to help/review but if no one step up it's unreasonable for me to
support those right now and I prefer to remove completely the support.

 The plan is to remove support in one month (July 12th) if there is no
volunteer to update the current code.

 Cheers,

-- 
Emmanuel Vadot <manu at bidouilliste.com> <manu at freebsd.org>