[Linker] PR33527 - Linker::LinkOnlyNeeded should import AppendingLinkage globals

Linker::LinkOnlyNeeded should always import globals with
AppendingLinkage.

This resolves PR33527.

Differential Revision: https://reviews.llvm.org/D34448

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310522 91177308-0d34-0410-b5e6-96231b3b80d8
11 files changed