Jit64: remove unused FlushMode enum
RegCache64: remove unused functions
RegCache64: move x?locks into register structs
RegCache64: Use std::array
RegCache64: devirtualize RegCache::Start
RegCache: merge fpr+gpr StoreFromRegister
RegCache: merge fpr+gpr BindToRegister
RegCache: make state clear optional on flushes
Jit64: Don't flush the regcache on bcx
Change register cache to using an enum to determine flush mode.
This is easier to identify what the flush is doing rather than a "true" as argument.
Add conditional register cache flushing to JIT64's bcctrx conditional route.
Add conditional register cache flushing to JIT64's bcx instruction.
Add conditional register cache flushing to JIT64's twx instruction.
Fix a few code style remarks.
Removes some casting of size_t to int.
Merge pull request #479 from Sonicadvance1/x86-regcache

Jit64 RegCache cleanup