MIPS64: add a flag for sim bad address debug to run tests faster.

New flag --sim-dbg-addr, defaults true, which is the default behavior
we have always used. Unaligned addresses or addresses near 0, drop us
into sim debugger.

But by passing --no-sim-dbg-addr to the test runner, we can make
the sim fail fast so these tests do not time out (slowly).

That makes the test suite run a lot faster.
MIPS64: Fix the output alignment in disassmebler.

Also remove tabs & adjust indents.
MIPS64: Remove hard tabs.

Whitespace only change, no code changes.
MIPS64: Fix LCodeGen::DoLoad/StoreKeyedExternalArray.