[tsan] Expect memmove interceptor to be called from memcpy

On OS X, memcpy and memmove are actually aliases of the same function, so the memmove interceptor can be invoked on a call to memcpy. This patch updates the tests to expect either memmove or memcpy on a stack trace.

Differential Revision: http://reviews.llvm.org/D14638

llvm-svn: 253077