stm32fsdev: Implement dcd_connect.

test/test/device/msc/test_msc_device.c

@@ -199,6 +199,7 @@ void setUp(void)
   if ( !tusb_inited() )
   {
     dcd_init_Expect(rhport);
+    dcd_connect_Expect(rhport);
     tusb_init();
   }
 

test/test/device/usbd/test_usbd.c

@@ -127,6 +127,7 @@ void setUp(void)
   {
     mscd_init_Expect();
     dcd_init_Expect(rhport);
+    dcd_connect_Expect(rhport);
     tusb_init();
   }
 }