Teensy 4.1 Ethernet support (#19801)

Marlin/src/gcode/gcode.cpp

@@ -766,6 +766,12 @@ void GcodeSuite::process_parsed_command(const bool no_ok/*=false*/) {
         case 540: M540(); break;                                  // M540: Set abort on endstop hit for SD printing
       #endif
 
+      #if HAS_ETHERNET
+        case 552: M552(); break;                                  // M552: Set IP address
+        case 553: M553(); break;                                  // M553: Set gateway
+        case 554: M554(); break;                                  // M554: Set netmask
+      #endif
+
       #if ENABLED(BAUD_RATE_GCODE)
         case 575: M575(); break;                                  // M575: Set serial baudrate
       #endif