Fix M876 when called from EP (#21210)

Marlin/src/feature/host_actions.cpp

@@ -143,24 +143,16 @@ void host_action(PGM_P const pstr, const bool eol) {
   //  - Dismissal of info
   //
   void host_response_handler(const uint8_t response) {
-    #ifdef DEBUG_HOST_ACTIONS
-      static PGMSTR(m876_prefix, "M876 Handle Re");
-      serialprintPGM(m876_prefix); SERIAL_ECHOLNPAIR("ason: ", host_prompt_reason);
-      serialprintPGM(m876_prefix); SERIAL_ECHOLNPAIR("sponse: ", response);
-    #endif
-    PGM_P msg = PSTR("UNKNOWN STATE");
     const PromptReason hpr = host_prompt_reason;
     host_prompt_reason = PROMPT_NOT_DEFINED;  // Reset now ahead of logic
     switch (hpr) {
       case PROMPT_FILAMENT_RUNOUT:
-        msg = PSTR("FILAMENT_RUNOUT");
         switch (response) {
 
           case 0: // "Purge More" button
             #if BOTH(HAS_LCD_MENU, ADVANCED_PAUSE_FEATURE)
               pause_menu_response = PAUSE_RESPONSE_EXTRUDE_MORE;  // Simulate menu selection (menu exits, doesn't extrude more)
             #endif
-            filament_load_host_prompt();                          // Initiate another host prompt. (NOTE: The loop in load_filament may also do this!)
             break;
 
           case 1: // "Continue" / "Disable Runout" button
@@ -178,23 +170,17 @@ void host_action(PGM_P const pstr, const bool eol) {
         break;
       case PROMPT_USER_CONTINUE:
         TERN_(HAS_RESUME_CONTINUE, wait_for_user = false);
-        msg = PSTR("FILAMENT_RUNOUT_CONTINUE");
         break;
       case PROMPT_PAUSE_RESUME:
-        msg = PSTR("LCD_PAUSE_RESUME");
         #if BOTH(ADVANCED_PAUSE_FEATURE, SDSUPPORT)
           extern const char M24_STR[];
           queue.inject_P(M24_STR);
         #endif
         break;
       case PROMPT_INFO:
-        msg = PSTR("GCODE_INFO");
         break;
       default: break;
     }
-    SERIAL_ECHOPGM("M876 Responding PROMPT_");
-    serialprintPGM(msg);
-    SERIAL_EOL();
   }
 
 #endif // HOST_PROMPT_SUPPORT

Marlin/src/feature/pause.cpp

@@ -259,7 +259,7 @@ bool load_filament(const float &slow_load_length/*=0*/, const float &fast_load_l
         unscaled_e_move(purge_length, ADVANCED_PAUSE_PURGE_FEEDRATE);
       }
 
-      TERN_(HOST_PROMPT_SUPPORT, filament_load_host_prompt()); // Initiate another host prompt. (NOTE: host_response_handler may also do this!)
+      TERN_(HOST_PROMPT_SUPPORT, filament_load_host_prompt()); // Initiate another host prompt.
 
       #if HAS_LCD_MENU
         if (show_lcd) {