DSP: Use completion event for ARAM interrupt
DSP: General cleanup. No behaviour change.
JIT64: faster implementation of mfcr
JIT64: faster + branchless crxxx
JIT64: faster implementation of mtcrf and mcrxr
JIT: cleanup unnecessary immedate size-checking logic

We do this in the emitter now, so this code isn't needed anymore.
Merge pull request #792 from booto/dsp-cleanup

DSP cleanup
JIT: avoid saving the PC on every store

Modify the backpatcher to store the PC in the trampolines.
Should be ~3.5% faster overall (measured on POV-RAY benchmark).
Merge pull request #746 from FioraAeterna/fastermtcrf

Improve performance of CR functions in JIT64
Merge pull request #807 from FioraAeterna/avoidpcstore

JIT: avoid saving the PC on every store
Merge pull request #831 from FioraAeterna/cleanupimm

JIT: cleanup unnecessary immedate size-checking logic