sim/usbhost: modify ctrlin return value

On success, zero (OK) is returned. On a failure, a negated errno value
is returned indicating the nature of the failure.

Signed-off-by: yangsong8 <yangsong8@xiaomi.com>

arch/sim/src/sim/sim_usbhost.c

@@ -569,7 +569,7 @@ static int sim_usbhost_ctrlin(struct usbhost_driver_s *drvr,
   nxsem_wait(&ep0info->iocsem);
   nxsem_destroy(&ep0info->iocsem);
 
-  return ep0info->xfrd;
+  return ep0info->xfrd < 0 ? ep0info->xfrd : OK;
 }
 
 /****************************************************************************