Remove tegra2 builders from config.
Remove tegra2 builders from config.

BUG=chromium-os:39042
TEST=Run all unit tests.

Change-Id: I5c465568d838be9c5e65f13c378d5fb7c79dd91a
Reviewed-on: https://gerrit.chromium.org/gerrit/43565
Reviewed-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Commit-Queue: David James <f231dc574bbeb62604660cbc162d1b8642a0a3af@chromium.org>
Tested-by: David James <f231dc574bbeb62604660cbc162d1b8642a0a3af@chromium.org>
Reviewed-by: Peter Mayo <3d31fdaf44dc55bb1b4f50b19df9bc879177d37a@chromium.org>

bpsinc-native/src_third_party_chromite,coreos/chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite,zhang0137/chromite,bpsinc-native/src_third_party_chromite,coreos/chromite,zhang0137/chromite,coreos/chromite,zhang0137/chromite