In the initial exec mode we always do a load to find the address of a variable.

In the initial exec mode we always do a load to find the address of a variable.
Before this patch in pic 32 bit code we would add the global base register
and not load from that address. This is a really old bug, but before the
introduction of the tls attributes we would never select initial exec for
pic code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159409 91177308-0d34-0410-b5e6-96231b3b80d8