[mlir] Only number the parent operation in Block::printAsOperand

[rriddle]

Summary

Blocks are numbered locally within a region, so numbering above the parent region is unnecessary.

mlir/lib/IR/AsmPrinter.cpp

 
 /// Print out the name of the block without printing its body.
 void Block::printAsOperand(raw_ostream &os, bool printType) {
   Operation *parentOp = getParentOp();
   if (!parentOp) {
     os << "<<UNLINKED BLOCK>>\n";
     return;
   }
-  // Get the top-level op.
-  while (auto *nextOp = parentOp->getParentOp())
-    parentOp = nextOp;
-
   AsmState state(parentOp);
   printAsOperand(os, state);
 }
 void Block::printAsOperand(raw_ostream &os, AsmState &state) {
   OperationPrinter printer(os, /*flags=*/llvm::None, state.getImpl());
   printer.printBlockName(this);
 }