PBQP/Graph.h: s/os/OS/ in @param. [-Wdocumentation]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202794 91177308-0d34-0410-b5e6-96231b3b80d8
PBQP/Graph.h: Prune @return in setNodeCosts, possibly copypasto. [-Wdocumentation]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202795 91177308-0d34-0410-b5e6-96231b3b80d8