[NFC][TableGen] Remove dead code.

Differential Revision: https://reviews.llvm.org/D151635

Author: LuoYuanke

llvm/utils/TableGen/GlobalISel/GIMatchTree.cpp

@@ -681,12 +681,7 @@ void GIMatchTreeVRegDefPartitioner::repartition(
       WantsEdge = true;
     }
 
-    bool isNotReg = false;
-    if (!WantsEdge && isNotReg) {
-      // If this leaf doesn't have an edge and we _don't_ want a register,
-      // then add it to partition 0.
-      addToPartition(false, Leaf.index());
-    } else if (!WantsEdge) {
+    if (!WantsEdge) {
       // If this leaf doesn't have an edge and we don't know what we want,
       // then add it to partition 0 and 1.
       addToPartition(false, Leaf.index());