[CodeGen] Attach function attributes to Objective-C and OpenMP

functions.

This commit fixes a bug in CGOpenMPRuntime.cpp and CGObjC.cpp where
some of the function attributes are not attached to newly created
functions.

rdar://problem/20828324

Differential Revision: http://reviews.llvm.org/D13928


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@251476 91177308-0d34-0410-b5e6-96231b3b80d8