Great news! The developers fixed the problem with systemd. It is no longer necessary to compile a kernel with SECCOMP support. I was able to boot ubuntu MATE 16.10 PowerPC with the stable longterm kernel 4.1.30 today.
Xubuntu 16.10 PowerPC with the new stable longterm kernel 4.1.31:
I was able to boot Julian's ubuntu MATE 16.04 from the USB flash drive with the new longterm kernel 4.1.31 and with the initrd.img-4.1.31. I use the label Ubuntu_16.04.
Please note: CFE firmware does not recognise USB devices on power-up unless they are connected to the first USB port which is reserved for the keyboard. Unless you have a USB hub connected to the first port which allows you to connect both the keyboard and USB disk, you will need to insert the USB disk AFTER you have entered CFE.
I released the stable longterm kernel 4.1.32 today.
New:
- Additional Btrfs options removed - Support for 3dfx Banshee or Voodoo3 (or later) graphics card removed because you can't boot the X1000 with a Voodoo graphics card. (see A1-X1000: 3dfx Voodoo4 4500 PCI test) - ChangeLog - Linux Git log
Please note: This kernel doesn't work with systemd on ubuntu MATE 16.10. If you use ubuntu MATE 16.10, please use the kernel 4.7-2 instead.
Please test Btrfs.
BTW, I have fantastic news! Darren integrates the Nemo motherboard to the official Linux kernel. He has rewritten the Nemo patch for the future kernel 4.8.