types/ptr: deprecate ptr.To, use Go 1.26 new

Updates #18682

Change-Id: I62f6aa0de2a15ef8c1435032c6aa74a181c25f8f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

hostinfo/hostinfo_darwin.go

@@ -10,7 +10,6 @@ import (
 	"path/filepath"
 
 	"golang.org/x/sys/unix"
-	"tailscale.com/types/ptr"
 )
 
 func init() {
@@ -19,7 +18,7 @@ func init() {
 }
 
 var (
-	lazyOSVersion = &lazyAtomicValue[string]{f: ptr.To(osVersionDarwin)}
+	lazyOSVersion = &lazyAtomicValue[string]{f: new(osVersionDarwin)}
 )
 
 func packageTypeDarwin() string {