[INLINER] allow inlining of address taken blocks

as long as their uses does not contain calls to functions that capture
the argument (potentially allowing the blockaddress to "escape" the
lifetime of the caller).

TODO:
- add more tests
- fix crash in llvm::updateCGAndAnalysisManagerForFunctionPass when
  invoking Transforms/Inline/blockaddress.ll

llvm-svn: 354079