[clang] less verbose logging of translation errors
[clang] less verbose logging of translation errors

Summary:
This was spammy, especially for errors which we already know about and are
caught by the frontend (then the error message would be displayed about a
translation error without context about what the error was).

Reviewed By: dulmarod

Differential Revision: D8640145

fbshipit-source-id: 8b8b8a7

facebook/infer,facebook/infer,facebook/infer,jvillard/infer,jvillard/infer,facebook/infer,jvillard/infer,jvillard/infer,facebook/infer,jvillard/infer,facebook/infer,facebook/infer,jvillard/infer,jvillard/infer