Nvidia made a mistake when porting their stuff to 4.4. In arm-gic.h you will see that a line #ifndefASSEMBLY appears after the “enum domain_gic_pm_event” declaration. The #ifndef should of course be before the declaration since enums are not valid assembly language either.
Moving the #ifndef should allow you to compile the file, however KVM still does not work on the TX2. The message in dmesg during boot is:
So it seems there is something missing from the Device Tree as well.
This reminds me that I should probably make a patch for all the mistakes I found and fixed in the 4.4 kernel sources and publish them somewhere. (There are other kernel features which do work but which can’t be compiled either with unpatched sources.)