[NFC] Fix typo in comment

Address comment in https://reviews.llvm.org/D137936

Differential Revision: https://reviews.llvm.org/D138124

Author: vfdff

llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

@@ -20605,7 +20605,7 @@ SDValue DAGCombiner::reduceBuildVecExtToExtBuildVec(SDNode *N) {
 
 // Simplify (build_vec (trunc $1)
 //                     (trunc (srl $1 half-width))
-//                     (trunc (srl $1 (2 * half-width))) …)
+//                     (trunc (srl $1 (2 * half-width))))
 // to (bitcast $1)
 SDValue DAGCombiner::reduceBuildVecTruncToBitCast(SDNode *N) {
   assert(N->getOpcode() == ISD::BUILD_VECTOR && "Expected build vector");