Recognise options to output dependency files and don't perform checks.
Report input file name when reporting a check failure so it is more obvious in large build logs.

Differential Revision: http://reviews.llvm.org/D10183

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@238928 91177308-0d34-0410-b5e6-96231b3b80d8