Move copying of global initializers below the cloning of functions.

The BlockAddress doesn't have access to the correct basic blocks until the
functions have been cloned. This causes the BlockAddress to point to the old
values. Just wait until the functions have been cloned before copying the
initializers.
PR13163

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194218 91177308-0d34-0410-b5e6-96231b3b80d8