[AArch64] Implement extshx and extsbx.
[AArch64] Implement cntlzwx.
[AArch64] Implement negx.
[AArch64] Implement mcrf.
[AArch64] Implement mtsr and mfsr
[AArch64] Implement mtsprin and mfsprin
[AArch64] Implement mfmsr
[AArch64] Implement twi and tw.
Fix some warnings on Linux
Android: Silence some more warnings.
JIT: flush a register if it won't be used for the rest of the block

This should dramatically reduce code size in the case of blocks with
lots of branches, and certainly doesn't hurt elsewhere either.

This can probably be improved a good bit through smarter tracking of register
usage, e.g. discarding registers that are going to be overwritten, but this
is a good start and should help reduce code size and register pressure.
Unlike that sort of change, this is a "safe" patch; it only flushes registers,
which can't affect correctness, unlike actually discarding data.

As part of this, refactor PPCAnalyst to support distinguishing between
float and integer registers (to properly handle instructions that access
both, like floating-point loads and stores).

Also update every instruction in the interpreter flags table I could find
that didn't have all the correct flags.
JIT: fix merged bclr with comex's BLR optimizations
Merge pull request #1152 from FioraAeterna/fixmergedbclr

JIT: fix merged bclr with comex's BLR optimizations
Merge pull request #1142 from lioncash/linucks

Fix some warnings on Linux
Merge pull request #1130 from Sonicadvance1/AArch64-jit-extXx

[AArch64] Implement instructions.
Replaced KillImmediate with BindToRegister in the tw instruction.  Fixes the error "WriteNormalOp - a1 and a2 cannot both be memory" which appeared on starting Monopoly Streets.
Merge pull request #1149 from rohit-n/android-warnings

Android: Silence some more warnings.
Merge pull request #1074 from FioraAeterna/earlyflush

JIT: flush a register if it won't be used for the rest of the block
Merge pull request #1153 from skidau/twx-bindtoreg

Replaced KillImmediate with BindToRegister in the tw instruction.