[arm] Drop SMMLS support.

[arm] Drop SMMLS support.

Apparently

 SMMLS r, b, c, a

computes

 r = ((a << 32) - b * c) >> 32

while the documentation is kinda misleading and states that it should
compute

 r = a - ((b * c) >> 32)

The actual behavior is kinda useless, so we drop the instruction again.

TEST=cctest,unittests
TBR=dcarney@chromium.org

Committed: https://code.google.com/p/v8/source/detail?r=24577

[Benedikt Meurer, 2014-10-14 07:47:08]

bmeurer@chromium.org changed reviewers:
+ dcarney@chromium.org

[Benedikt Meurer, 2014-10-14 07:47:40]

Committed patchset #1 (id:1) manually as 24577 (tree was closed).