ARROW-13548: [C++] Implement temporal difference kernels

Co-authored-by: Rok Mihevc <rok@mihevc.org>

Author: lidavidm

cpp/src/arrow/array/diff.cc

@@ -464,7 +464,7 @@ class MakeFormatterImpl {
     impl_ = [](const Array& array, int64_t index, std::ostream* os) {
       auto month_day_nanos =
           checked_cast<const MonthDayNanoIntervalArray&>(array).Value(index);
-      *os << month_day_nanos.months << "m" << month_day_nanos.days << "d"
+      *os << month_day_nanos.months << "M" << month_day_nanos.days << "d"
           << month_day_nanos.nanoseconds << "ns";
     };
     return Status::OK();

cpp/src/arrow/array/diff_test.cc

@@ -507,7 +507,7 @@ TEST_F(DiffTest, UnifiedDiffFormatter) {
   target_ = ArrayFromJSON(month_day_nano_interval(), R"([])");
   AssertDiffAndFormat(R"(
 @@ -0, +0 @@
--2m3d1ns
+-2M3d1ns
 )");
 
   // lists

cpp/src/arrow/compute/kernels/codegen_internal.h

@@ -923,6 +923,10 @@ using ScalarBinaryEqualTypes = ScalarBinary<OutType, ArgType, ArgType, Op>;
 template <typename OutType, typename ArgType, typename Op>
 using ScalarBinaryNotNullEqualTypes = ScalarBinaryNotNull<OutType, ArgType, ArgType, Op>;
 
+template <typename OutType, typename ArgType, typename Op>
+using ScalarBinaryNotNullStatefulEqualTypes =
+    ScalarBinaryNotNullStateful<OutType, ArgType, ArgType, Op>;
+
 }  // namespace applicator
 
 // ----------------------------------------------------------------------