migration: drop colo_incoming_thread from MigrationIncomingState

have_colo_incoming_thread variable is unused. colo_incoming_thread can
be local.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Message-Id: <20230428194928.1426370-6-vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>

migration/migration.c

@@ -544,21 +544,22 @@ process_incoming_migration_co(void *opaque)
 
     /* we get COLO info, and know if we are in COLO mode */
     if (!ret && migration_incoming_colo_enabled()) {
+        QemuThread colo_incoming_thread;
+
         /* Make sure all file formats throw away their mutable metadata */
         bdrv_activate_all(&local_err);
         if (local_err) {
             error_report_err(local_err);
             goto fail;
         }
 
-        qemu_thread_create(&mis->colo_incoming_thread, "COLO incoming",
+        qemu_thread_create(&colo_incoming_thread, "COLO incoming",
              colo_process_incoming_thread, mis, QEMU_THREAD_JOINABLE);
-        mis->have_colo_incoming_thread = true;
         qemu_coroutine_yield();
 
         qemu_mutex_unlock_iothread();
         /* Wait checkpoint incoming thread exit before free resource */
-        qemu_thread_join(&mis->colo_incoming_thread);
+        qemu_thread_join(&colo_incoming_thread);
         qemu_mutex_lock_iothread();
         /* We hold the global iothread lock, so it is safe here */
         colo_release_ram_cache();

migration/migration.h

@@ -162,8 +162,6 @@ struct MigrationIncomingState {
 
     int state;
 
-    bool have_colo_incoming_thread;
-    QemuThread colo_incoming_thread;
     /* The coroutine we should enter (back) after failover */
     Coroutine *migration_incoming_co;
     QemuSemaphore colo_incoming_sem;