x86jit: Consistently use mips_.
x86jit: Use the shorter MDisp() offset for andLink.
x86jit: Pad linked exits with breakpoints.

So that we don't get garbage, and so we see if we end up there.
jit: Invalidate blocks even if they end unevenly.

This allows blocks to start and end where ever they need, which should be
good for replacements and for continuing.
x86jit: Add proxy blocks for continuing.
armjit: Add proxy blocks for continuing.
jit: Optimize proxy block lookup from address.

It was really slow before with enough proxy blocks.
jit: Fix a possible infinite loop in invalidation.
jit: Remove from the block map more carefully.
jit: Improve performance of clearing jit.
x86jit: Centralize continuing logic.
Merge pull request #6999 from unknownbrackets/jit-minor

Clean up jit invalidation with replaced and continued blocks