Remove per-device token migration added in #89

This is causing cyclic import pain. Remove it, rather than port it to
the newer migration infrastructure.

This means that users must run the migration before upgrading to the
any version which includes this change.

cmd/syncv3/main.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"context"
 	"flag"
 	"fmt"
 	"log"
@@ -85,7 +84,6 @@ func defaulting(in, dft string) string {
 }
 
 func main() {
-	ctx := context.Background()
 	fmt.Printf("Sync v3 [%s] (%s)\n", version, GitCommit)
 	sync2.ProxyVersion = version
 	syncv3.Version = fmt.Sprintf("%s (%s)", version, GitCommit)
@@ -190,11 +188,6 @@ func main() {
 		}
 	}
 
-	err := sync2.MigrateDeviceIDs(ctx, args[EnvServer], args[EnvDB], args[EnvSecret], true)
-	if err != nil {
-		panic(err)
-	}
-
 	maxConnsInt, err := strconv.Atoi(args[EnvMaxConns])
 	if err != nil {
 		panic("invalid value for " + EnvMaxConns + ": " + args[EnvMaxConns])