pkg/platform: remove deprecated OSType const

This const was deprecated in 5c78cbd3be7b782c1cc81825adf2a2595317a929, which
is part of the v24.0.0 release, so we can remove it from master.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

pkg/platform/platform.go

@@ -3,8 +3,6 @@
 package platform // import "github.com/docker/docker/pkg/platform"
 
 import (
-	"runtime"
-
 	"github.com/sirupsen/logrus"
 )
 
@@ -17,12 +15,6 @@ import (
 // when running a "linux/386" compiled binary on "linux/amd64" hardware.
 var Architecture string
 
-// OSType holds the runtime operating system type of the process. It is
-// an alias for [runtime.GOOS].
-//
-// Deprecated: use [runtime.GOOS] instead.
-const OSType = runtime.GOOS
-
 func init() {
 	var err error
 	Architecture, err = runtimeArchitecture()