[Driver] Suggest valid integrated tools
Summary:
There are only two valid integrated Clang driver tools: `-cc1` and
`-cc1as`. If a user asks for an unknown tool, such as `-cc1asphalt`,
an error message is displayed to indicate that there is no such tool,
but the message doesn't indicate what the valid options are.
Include the valid options in the error message.
Test Plan: `check-clang`
Reviewers: sepavloff, bkramer, phosek
Reviewed By: bkramer
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D42004
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@322517
91177308-0d34-0410-b5e6-
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