[mlir] Take ValueRange instead of ArrayRef<Value> in StructuredIndexed

[ftynse]

Summary

This was likely overlooked when ValueRange was first introduced. There is no
reason why StructuredIndexed needs specifically an ArrayRef so use ValueRange
for better type compatibility with the rest of the APIs.

mlir/include/mlir/EDSC/Builders.h

TemplatedIndexedValue operator()(Value index) {
     TemplatedIndexedValue res(value);
     res.indices.push_back(index);
     return res;
   }
   template <typename... Args>
   TemplatedIndexedValue operator()(Value index, Args... indices) {
     return TemplatedIndexedValue(value, index).append(indices...);
   }
-  TemplatedIndexedValue operator()(ArrayRef<Value> indices) {
+  TemplatedIndexedValue operator()(ValueRange indices) {
     return TemplatedIndexedValue(value, indices);
   }
 
   /// Emits a `store`.
   Store operator=(const TemplatedIndexedValue &rhs) {
     return Store(rhs, value, indices);
   }
   Store operator=(Value rhs) { return Store(rhs, value, indices); }
public:
   Value ugt(TemplatedIndexedValue e) {
     return ugt(*this, static_cast<Value>(e));
   }
   Value uge(TemplatedIndexedValue e) {
     return uge(*this, static_cast<Value>(e));
   }
 
 private:
-  TemplatedIndexedValue(Value value, ArrayRef<Value> indices)
+  TemplatedIndexedValue(Value value, ValueRange indices)
       : value(value), indices(indices.begin(), indices.end()) {}
 
   TemplatedIndexedValue &append() { return *this; }
 
   template <typename T, typename... Args>
   TemplatedIndexedValue &append(T index, Args... indices) {
     this->indices.push_back(static_cast<Value>(index));
     append(indices...);