JIT: simpler fallback conditions for load/store float

I wasn't really thinking when I wrote these; d/s are for float registers, not
gprs.
Merge pull request #1101 from FioraAeterna/fixfallbacks

JIT: simpler fallback conditions for load/store float
[AArch64] Implement a bunch of integer instructions
16 new instructions for AArch64.
Fix some indention on AArch64 JIT.