Reset CustomMsg when Command in progress is None

When a Progress report is started, we set the CustomMsg to MMUProgress.

But there was an issue where, once the reported "Progress" action was done.
We did not reset the CustomMsg to Status. So if we are printing from the
SD card, the file name is not displayed on the LCD.

Firmware/mmu2_reporting.cpp

@@ -262,8 +262,16 @@ void ReportErrorHook(uint16_t ec, uint8_t res) {
 }
 
 void ReportProgressHook(CommandInProgress cip, uint16_t ec) {
-    custom_message_type = CustomMsg::MMUProgress;
-    lcd_setstatuspgm( _T(ProgressCodeToText(ec)) );
+    if (cip != CommandInProgress::NoCommand)
+    {
+        custom_message_type = CustomMsg::MMUProgress;
+        lcd_setstatuspgm( _T(ProgressCodeToText(ec)) );
+    } else {
+        // If there is no command in progress we can display other
+        // useful information such as the name of the SD file 
+        // being printed
+        custom_message_type = CustomMsg::Status;
+    }
 }
 
 } // namespace MMU2