hmp: acquire aio_context in hmp_qemu_io

Acquire aio context before run command, this is mandatory for unit tests.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

hmp.c

@@ -1955,7 +1955,12 @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict)
 
     blk = blk_by_name(device);
     if (blk) {
+        AioContext *aio_context = blk_get_aio_context(blk);
+        aio_context_acquire(aio_context);
+
         qemuio_command(blk, command);
+
+        aio_context_release(aio_context);
     } else {
         error_set(&err, ERROR_CLASS_DEVICE_NOT_FOUND,
                   "Device '%s' not found", device);