* VFP instructions were not getting fuzzed due to matching coprocessor instructions (as invalid instructions)
* Fix VPOP writeback for doubles when (imm8 & 1) == 1
* Do not accidentally fuzz unimplemented unconditional instructions
Now that we fuzz against Unicorn, we aren't just restricted to VFPv2.
VFPv3 and VFPv4 facilities can now be implemented. This renames
constructs mentioning VFPv2 to just refer to VFP.