only invoke tuh_msc_umount_cb() if needed

src/class/hid/hid_host.c

@@ -241,7 +241,7 @@ void hidh_close(uint8_t dev_addr)
   hidh_device_t* hid_dev = get_dev(dev_addr);
   if (tuh_hid_umount_cb)
   {
-    for ( uint8_t inst = 0; inst < hid_dev->inst_count; inst++) tuh_hid_umount_cb(dev_addr, inst);
+    for ( uint8_t inst = 0; inst < hid_dev->inst_count; inst++ ) tuh_hid_umount_cb(dev_addr, inst);
   }
 
   tu_memclr(hid_dev, sizeof(hidh_device_t));

src/class/msc/msc_host.c

@@ -297,10 +297,11 @@ void msch_init(void)
 void msch_close(uint8_t dev_addr)
 {
   msch_interface_t* p_msc = get_itf(dev_addr);
-  tu_memclr(p_msc, sizeof(msch_interface_t));
 
   // invoke Application Callback
-  if (tuh_msc_umount_cb) tuh_msc_umount_cb(dev_addr);
+  if (p_msc->mounted && tuh_msc_umount_cb) tuh_msc_umount_cb(dev_addr);
+
+  tu_memclr(p_msc, sizeof(msch_interface_t));
 }
 
 bool msch_xfer_cb(uint8_t dev_addr, uint8_t ep_addr, xfer_result_t event, uint32_t xferred_bytes)