[asan] Specialize the initialization-bug.cc testcase for Darwin (it needs a...

[asan] Specialize the initialization-bug.cc testcase for Darwin (it needs a deployment target of 10.11+)

The ODR detection in initialization-bug.cc now works on Darwin (due to the recently enabled "live globals" on-by-default), but only if the deployment target is 10.11 or higher. Let's adjust the testcases.

Differential Revision: https://reviews.llvm.org/D26927

llvm-svn: 287581