ath79: move 8/32 boards to tiny subtarget

[Sven Roederer]

Hi,

not sure if this has been discussed before.
I recently worked with some 8/32 boards (Ubiquiti Nanostation M (XM), TPLink 
WR842 v2)  for our Freifunk-project and realized that the low RAM situation 
requires quite different handling than the full boards (8+/64+).

I wonder if there is a reason to not move the boards, which are affected by 
the 4/32MB warning also, to the ath79-tiny target?

Sven