This revision fixes the import of LLVM IR to handle debug metadata with
cyclic dependencies. It deletes the elements list of the composite type
if a cyclic dependency is detected. The revision is meant as a band aid
to avoid infinite recursion during the import of cyclic debug metadata.
Long term solutions are currently discussed here:
https://discourse.llvm.org/t/handling-cyclic-dependencies-in-debug-info/67526/4
Reviewed By: Dinistro
Differential Revision: https://reviews.llvm.org/D142086