tree e3fe7b4b614daaa25052a7221ffb27968bfc80c9
parent 3615dcb30cb1db4e61dea229d70a360b26849475
author Dan Willemsen <dwillemsen@google.com> 1508970050 -0700
committer Dan Willemsen <dwillemsen@google.com> 1508970050 -0700

Switch instruction_set to *string

So that the contents gets replaced when prepended/appended instead of
merged.

Test: Set instruction_set in a cc_defaults, and in a module.
Change-Id: I0f2c789231d89efa1ab053f9dc118cd19f11b0e6