Updated MMU serial status message

- Shown during bootup
- Shown on LCD menue MMU [ON|OFF]
- Shown using `M709`
- Shown when `Disable`d with MMU ERROR FW UPDATE NEEDED

Firmware/Marlin_main.cpp

@@ -1125,6 +1125,7 @@ void setup()
 	if (eeprom_init_default_byte((uint8_t *)EEPROM_MMU_ENABLED, 0)) {
 		MMU2::mmu2.Start();
 	}
+	MMU2::mmu2.Status();
 	SpoolJoin::spooljoin.initSpoolJoinStatus();
 
 	//SERIAL_ECHOPAIR("Active sheet before:", static_cast<unsigned long int>(eeprom_read_byte(&(EEPROM_Sheets_base->active_sheet))));
@@ -8640,7 +8641,7 @@ Sigma_Exit:
                 break;
             }
         }
-        printf_P(_n("MMU state:%d\n"), MMU2::mmu2.Enabled());
+    MMU2::mmu2.Status();
     }
     break;
 

Firmware/mmu2.cpp

@@ -12,6 +12,9 @@
 #include "strlen_cx.h"
 #include "SpoolJoin.h"
 
+#include "messages.h"
+#include "language.h"
+
 #ifdef __AVR__
 // As of FW 3.12 we only support building the FW with only one extruder, all the multi-extruder infrastructure will be removed.
 // Saves at least 800B of code size
@@ -52,6 +55,17 @@ MMU2::MMU2()
     , tmcFailures(0) {
 }
 
+void MMU2::Status() {
+    // Useful information to see during bootup and change state
+    SERIAL_ECHOPGM("MMU is ");
+    uint8_t status = eeprom_init_default_byte((uint8_t*)EEPROM_MMU_ENABLED, 0);
+    if (status == 1) {
+        SERIAL_ECHOLNRPGM(_O(MSG_ON));
+    } else {
+        SERIAL_ECHOLNRPGM(_O(MSG_OFF));
+    }
+}
+
 void MMU2::Start() {
     mmu2Serial.begin(MMU_BAUD);
 

Firmware/mmu2.h

@@ -39,6 +39,9 @@ public:
     /// Stops the protocol logic, closes the UART, powers OFF the MMU
     void Stop();
 
+    /// Serial output of MMU state
+    void Status();
+
     inline xState State() const { return state; }
 
     inline bool Enabled() const { return State() == xState::Active; }

Firmware/mmu2_reporting.cpp

@@ -347,6 +347,7 @@ void TryLoadUnloadReporter::DumpToSerial(){
 /// Disables MMU in EEPROM
 void DisableMMUInSettings() {
     eeprom_update_byte((uint8_t *)EEPROM_MMU_ENABLED, false);
+    mmu2.Status();
 }
 
 void IncrementLoadFails(){

Firmware/ultralcd.cpp

@@ -4093,6 +4093,7 @@ static void mmu_enable_switch()
     }
 
     eeprom_toggle((uint8_t *)EEPROM_MMU_ENABLED);
+    MMU2::mmu2.Status();
 }
 
 static void SETTINGS_SILENT_MODE()