R600: Fix R600ControlFlowFinalizer not considering VTX_READ 128 bit dst reg

Patch by: Vincent Lejeune

https://bugs.freedesktop.org/show_bug.cgi?id=64877

NOTE: This is a candidate for the 3.3 branch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182600 91177308-0d34-0410-b5e6-96231b3b80d8