We already verified the primary module map file (either the one that
defines the top-level module, or the one that allows inferring it if it
is an inferred framework module). Now we also verify any other module
map files that define submodules, such as when there is a
module.private.modulemap file.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@215455 91177308-0d34-0410-b5e6-96231b3b80d8