migration: Create multifd_bytes ram_counter

This will include how many bytes they are sent through multifd.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
diff --git a/migration/migration.c b/migration/migration.c
index 264f3ce..2680ba2 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -708,6 +708,7 @@
     info->ram->dirty_sync_count = ram_counters.dirty_sync_count;
     info->ram->postcopy_requests = ram_counters.postcopy_requests;
     info->ram->page_size = qemu_target_page_size();
+    info->ram->multifd_bytes = ram_counters.multifd_bytes;
 
     if (migrate_use_xbzrle()) {
         info->has_xbzrle_cache = true;