Fix buildbot build script.

Got broken after:
- https://android-review.googlesource.com/c/platform/art/+/1193736
  (*-target targets don't exist anymore)
- https://android-review.googlesource.com/c/platform/build/+/1146736
  (remove ld.config.txt as a build target).

Test: tools/buildbot-build.sh
Change-Id: I99819de2ec6eb44b5e1953dfb94d3a05b59fa167
1 file changed