[rfc] moving sys/mips/atheros to sys/mips/ar71xx, and moving sys/mips/atheros/ar531x to sys/mips/ar531x

[Adrian Chadd]

hiya,

The atheros MIPS stuff is a little badly organised. I'd like to
reorganise it a little:

* sys/mips/atheros - is the only shared bits (ie, the bus space code)
* sys/mips/ar71xx - atheros 71xx and later
* sys/mips/ar531x - the earlier generation mips4kc cores

It'll require a bit of svn mv'ing things around and will likely upset
anyone with branches, but I'd rather do this shuffling before
12.0-RELEASE is cut.

Any objections?



-adrian