build: convert to go:build directives (#2664)

binding/binding.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT style
 // license that can be found in the LICENSE file.
 
+//go:build !nomsgpack
 // +build !nomsgpack
 
 package binding

binding/binding_msgpack_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT style
 // license that can be found in the LICENSE file.
 
+//go:build !nomsgpack
 // +build !nomsgpack
 
 package binding

binding/binding_nomsgpack.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT style
 // license that can be found in the LICENSE file.
 
+//go:build nomsgpack
 // +build nomsgpack
 
 package binding

binding/msgpack.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT style
 // license that can be found in the LICENSE file.
 
+//go:build !nomsgpack
 // +build !nomsgpack
 
 package binding

binding/msgpack_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a MIT style
 // license that can be found in the LICENSE file.
 
+//go:build !nomsgpack
 // +build !nomsgpack
 
 package binding