rdma: remove check on time_spent when calculating mbs

Within the if statement, time_spent is assured to be non-zero.

This patch just removes the check on time_spent when calculating mbs.
Signed-off-by: NWei Yang <richard.weiyang@gmail.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

migration/migration.c

@@ -1691,8 +1691,8 @@ static void *migration_thread(void *opaque)
             double bandwidth = (double)transferred_bytes / time_spent;
             max_size = bandwidth * migrate_max_downtime() / 1000000;
 
-            s->mbps = time_spent ? (((double) transferred_bytes * 8.0) /
-                    ((double) time_spent / 1000.0)) / 1000.0 / 1000.0 : -1;
+            s->mbps = (((double) transferred_bytes * 8.0) /
+                    ((double) time_spent / 1000.0)) / 1000.0 / 1000.0;
 
             trace_migrate_transferred(transferred_bytes, time_spent,
                                       bandwidth, max_size);