I compiled the third update of the stable kernel 4.9 today.
New:
Download: vmlinux-4.9.3-AmigaONE_X1000.tar.gz
BTW, I was able to update ubuntu MATE 17.04 today and I got the new Mesa 13.0.3.

Screenshot of ubuntu MATE 17.04 PowerPC with the new Mesa 13.0.3 and with the stable kernel 4.9.3:

Cheers,
Christian