[asan] Undo special treatment of linkonce_odr and weak_odr

Summary:
On non-Windows these are already removed by ShouldInstrumentGlobal.
On Window we will wait until we get actual issues with that.

Reviewers: pcc

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D55899

llvm-svn: 349707