Merge pull request #970 from Bastian-Krause/bst/qemu-disk-vexpress

driver/qemudriver: fix disk attribute for vexpress-a9 machine

Author: jluebbe

labgrid/driver/qemudriver.py

@@ -121,7 +121,7 @@ def on_activate(self):
                 self._cmd.append(
                     f"if=sd,format={disk_format},file={disk_path},id=mmc0")
                 boot_args.append("root=/dev/mmcblk0p1 rootfstype=ext4 rootwait")
-            if self.machine == "q35":
+            elif self.machine == "q35":
                 self._cmd.append("-drive")
                 self._cmd.append(
                     f"if=virtio,format={disk_format},file={disk_path}")