MIPS64: madd_d loses precision on loongson 3A chip.

On Loongson 3A chip, madd_d is different from mips64, this will cause failure
test/benchmarks/sunspider/3d-cube. Synthesize madd from mul and add.

TEST: benchmarks/sunspider/3d-cube
      benchmarks/sunspider/3d-raytrace
      benchmarks/sunspider/access-nbody
MIPS64: Init TickSample.state on mips64 HW.

TEST: cctest/**/*WithProfiler
MIPS64: Restore default value of FLAG_code_comments.
MIPS64: Fix stack overflow on simulator when large number of locals are allocated.

TEST=mjsunit/limit-locals.js
BUG=
MIPS64: Silence all warnings in simulator.

(cherry picked from commit b6c1dcd302984dfc4572cdb715afa000e9928a8a)
MIPS64: Remove use of FLAG_sim_dbg_addr.

This removes the command line flag, which sped up test runs back the days
we had lots of unaligned errors.

More cleanup is still needed here.

Also, an un-related whitespace error is fixed.
MIPS64: Rename build target to mips64el.

This new name matches gnu usage, and what will be done in Android.
This name should be used in Chromium build system also.

(old name mipsel64).
MIPS64: Fix some features on HW.
MIPS64: Fix kFPUInvalidResult.

TEST: cctest/test-assembler-mips64/MIPS14
MIPS64: Add disassembler and macro-assembler cctests.
MIPS64: Add operands for smi untagging in macro-assembler.
MIPS64: Add SmiLoadUntag(), SmiLoadScale(), SmiScale(), etc.

Intent is to allow Loading, Untagging, and Shifting/Scaling to
be combined. This should allow common source for mips32 & mips64
for these operations.

Though unifying the ports is no longer a short-term goal, these
changes should improve readability, even if just used on mips64.

Note that the optimizations around these are different for mips32
and mips64, and the intent is to minimize total instructions on
both platforms.

Includes one example usage from Dusan's prior CL.
MIPS64: Fix TODO smi ops to use SmiUntag, SmiScale.

These are the simple, mechanical cases. No optimization
is achieved (as we could with SmiLoadUntag).