Trim unneeded output.
Fix test suite name display.
Further CallerAndCallee, etc. changes.

Strip more usages (explicit or implicit) of CallerAndCallee, EnterAndExit.
Improve caller-context instrumentation test.

The DES_set_key function actually requires caller-side instrumentation: we're going to assume that we can't modify the modules that go into building lib crypto.
Trivial: slight clarity improvement.

No functional change: whenever we skip 'ModifiedIR = true', it's only because we've previously done something that would already have set the flag.
Promote this check to an assertion.
Make llvm-lit test output quieter.