Log an error when vfpu swizzle is used badly.
Add TEMP0 fpu regs to x86 like in armjit.

But... will probably need more and the ability to swap into memory
if we want to deal with prefixes.
Enable VDot and Vec3 in x86 jit.
Discard temp regs right away, some helper funcs.
Optimize VDot and VecDo3 to avoid temporaries.
Fix VDot returning -0.0 in x86 jit.
Merge pull request #707 from unknownbrackets/jit-vfpu

Copy over temp fpu regs, enable VecDo3/VDot