There is now an ‘official’ fix for the 4.10-rc1 compile failure with ARM64/aarch64, from Al Viro, and the patch itself is available here:

https://git.kernel.org/cgit/linux/kernel/git/viro/vfs.git/commit/?h=arm64-fix&id=b4b8664d291ac1998e0f0bcdc96b6397f0fe68b3

I have applied this to kernel 4.10-rc1 on the Odroid C2, and the kernel compiles successfully..

Robert Gadsdon.   December 27, 2016.