[mlir][spirv] Add convenience builders for AddICarry and SubIBorrow

[kuhar]

Summary

This is so that we do not have to spell out long structure types every
time we create these ops.

[antiagainst]

Cool, thanks for this!

mlir/include/mlir/Dialect/SPIRV/IR/SPIRVArithmeticOps.td

let arguments = (ins
     SPV_ScalarOrVectorOf<SPV_Integer>:$operand1,
     SPV_ScalarOrVectorOf<SPV_Integer>:$operand2
   );
 
   let results = (outs
     SPV_AnyStruct:$result
   );
 
+  let builders = [
+    OpBuilder<(ins "Value":$operand1, "Value":$operand2), [{
+      build($_builder, $_state,
+            ::mlir::spirv::StructType::get({operand1.getType(), operand1.getType()}),
+            operand1, operand2);
+    }]>
+  ];
+
   let hasVerifier = 1;
 }
 
 // -----
 
 def SPV_IMulOp : SPV_ArithmeticBinaryOp<"IMul",
                                         SPV_Integer,
                                         [Commutative, UsableInSpecConstantOp]> {
let arguments = (ins
     SPV_ScalarOrVectorOf<SPV_Integer>:$operand1,
     SPV_ScalarOrVectorOf<SPV_Integer>:$operand2
   );
 
   let results = (outs
     SPV_AnyStruct:$result
   );
 
+  let builders = [
+    OpBuilder<(ins "Value":$operand1, "Value":$operand2), [{
+      build($_builder, $_state,
+            ::mlir::spirv::StructType::get({operand1.getType(), operand1.getType()}),
+            operand1, operand2);
+    }]>
+  ];
+
   let hasVerifier = 1;
 }
 
 // -----
 
 def SPV_SDivOp : SPV_ArithmeticBinaryOp<"SDiv",
                                         SPV_Integer,
                                         [UsableInSpecConstantOp]> {

mlir/lib/Conversion/ArithmeticToSPIRV/ArithmeticToSPIRV.cpp

 //===----------------------------------------------------------------------===//
 // AddICarryOpPattern
 //===----------------------------------------------------------------------===//
 
 LogicalResult
 AddICarryOpPattern::matchAndRewrite(arith::AddUICarryOp op, OpAdaptor adaptor,
                                     ConversionPatternRewriter &rewriter) const {
   Type dstElemTy = adaptor.getLhs().getType();
-  auto resultTy = spirv::StructType::get({dstElemTy, dstElemTy});
-
   Location loc = op->getLoc();
   Value result = rewriter.create<spirv::IAddCarryOp>(
-      loc, resultTy, adaptor.getLhs(), adaptor.getRhs());
+      loc, adaptor.getLhs(), adaptor.getRhs());
 
   Value sumResult = rewriter.create<spirv::CompositeExtractOp>(
       loc, result, llvm::makeArrayRef(0));
   Value carryValue = rewriter.create<spirv::CompositeExtractOp>(
       loc, result, llvm::makeArrayRef(1));
 
   // Convert the carry value to boolean.
   Value one = spirv::ConstantOp::getOne(dstElemTy, loc, rewriter);