OSSA: Allow BasicBlockUtils getEdgeArgs to create guaranteed phis

For switch_enum and dynamic_method_br

Author: atrick

lib/SIL/Utils/BasicBlockUtils.cpp

@@ -174,7 +174,8 @@ void swift::getEdgeArgs(TermInst *T, unsigned edgeIdx, SILBasicBlock *newEdgeBB,
     if (!succBB->getNumArguments())
       return;
     args.push_back(newEdgeBB->createPhiArgument(
-        succBB->getArgument(0)->getType(), OwnershipKind::Owned));
+        succBB->getArgument(0)->getType(),
+        succBB->getArgument(0)->getOwnershipKind()));
     return;
   }
 
@@ -186,7 +187,8 @@ void swift::getEdgeArgs(TermInst *T, unsigned edgeIdx, SILBasicBlock *newEdgeBB,
     if (!succBB->getNumArguments())
       return;
     args.push_back(newEdgeBB->createPhiArgument(
-        succBB->getArgument(0)->getType(), OwnershipKind::Owned));
+        succBB->getArgument(0)->getType(),
+        succBB->getArgument(0)->getOwnershipKind()));
     return;
   }