Save/restore Relative modes in Power-Loss Recovery (#13501)

Marlin/src/feature/power_loss_recovery.cpp

       info.retract_hop = fwretract.current_hop;
     #endif
 
+    //relative mode
+    info.relative_mode = relative_mode;
+    info.relative_modes_e = gcode.axis_relative_modes[E_AXIS];
+
     // Commands in the queue
     info.commands_in_queue = save_queue ? commands_in_queue : 0;
     info.cmd_queue_index_r = cmd_queue_index_r;
   sprintf_P(cmd, PSTR("G1 F%d"), info.feedrate);
   gcode.process_subcommands_now(cmd);
 
+  //relative mode
+  if (info.relative_mode) relative_mode = true;
+  if (info.relative_modes_e) gcode.axis_relative_modes[E_AXIS] = true;
+
   // Process commands from the old pending queue
   uint8_t c = info.commands_in_queue, r = info.cmd_queue_index_r;
   for (; c--; r = (r + 1) % BUFSIZE)

Marlin/src/feature/power_loss_recovery.h

     #endif
   #endif
 
+  // Relative mode
+  bool relative_mode, relative_modes_e;
+
   // Command queue
   uint8_t commands_in_queue, cmd_queue_index_r;
   char command_queue[BUFSIZE][MAX_CMD_SIZE];