Saves having it in several places.
Change-Id: I329e1bf4dd4a7f51396e36e2604280fcca32b58c
Reviewed-on: https://boringssl-review.googlesource.com/16026
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>