Use const parameters instead of static casting

Alternative fix to #3149

Marlin/dogm_lcd_implementation.h

@@ -169,7 +169,7 @@ char lcd_print(char c) {
   }
 }
 
-char lcd_print(char* str) {
+char lcd_print(const char* str) {
   char c;
   int i = 0;
   char n = 0;
@@ -508,7 +508,7 @@ static void _drawmenu_setting_edit_generic(bool isSelected, uint8_t row, const c
 #define lcd_implementation_drawmenu_setting_edit_callback_long5(sel, row, pstr, pstr2, data, minValue, maxValue, callback) lcd_implementation_drawmenu_setting_edit_generic(sel, row, pstr, ftostr5(*(data)))
 #define lcd_implementation_drawmenu_setting_edit_callback_bool(sel, row, pstr, pstr2, data, callback) lcd_implementation_drawmenu_setting_edit_generic_P(sel, row, pstr, (*(data))?PSTR(MSG_ON):PSTR(MSG_OFF))
 
-void lcd_implementation_drawedit(const char* pstr, char* value) {
+void lcd_implementation_drawedit(const char* pstr, const char* value) {
   uint8_t rows = 1;
   uint8_t lcd_width = LCD_WIDTH, char_width = DOG_CHAR_WIDTH;
   uint8_t vallen = lcd_strlen(value);

Marlin/ultralcd.cpp

@@ -516,7 +516,7 @@ void lcd_set_home_offsets() {
         babystepsTodo[axis] += distance;
       #endif
     }
-    if (lcdDrawUpdate) lcd_implementation_drawedit(msg, (char*)"");
+    if (lcdDrawUpdate) lcd_implementation_drawedit(msg, PSTR(""));
     if (LCD_CLICKED) lcd_goto_previous_menu();
   }
 
@@ -1715,7 +1715,7 @@ void lcd_init() {
   #endif
 }
 
-int lcd_strlen(char* s) {
+int lcd_strlen(const char* s) {
   int i = 0, j = 0;
   while (s[i]) {
     if ((s[i] & 0xc0) != 0x80) j++;
@@ -2397,7 +2397,7 @@ char* ftostr52(const float& x) {
    * MBL Move to mesh starting point
    */
   static void _lcd_level_bed_homing() {
-    if (lcdDrawUpdate) lcd_implementation_drawedit(PSTR("XYZ"), (char*)"Homing");
+    if (lcdDrawUpdate) lcd_implementation_drawedit(PSTR("XYZ"), PSTR("Homing"));
     if (axis_known_position[X_AXIS] && axis_known_position[Y_AXIS] && axis_known_position[Z_AXIS]) {
       current_position[Z_AXIS] = MESH_HOME_SEARCH_Z;
       plan_set_position(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS]);

Marlin/ultralcd.h

@@ -5,7 +5,7 @@
 #if ENABLED(ULTRA_LCD)
   #include "buzzer.h"
 
-  int lcd_strlen(char* s);
+  int lcd_strlen(const char* s);
   int lcd_strlen_P(const char* s);
   void lcd_update();
   void lcd_init();

Marlin/ultralcd_implementation_hitachi_HD44780.h

@@ -407,7 +407,7 @@ char lcd_printPGM(const char* str) {
   return n;
 }
 
-char lcd_print(char* str) {
+char lcd_print(const char* str) {
   char c, n = 0;
   unsigned char i = 0;
   while ((c = str[i++])) n += charset_mapper(c);
@@ -825,7 +825,7 @@ static void lcd_implementation_drawmenu_setting_edit_generic_P(bool sel, uint8_t
 #define lcd_implementation_drawmenu_setting_edit_callback_long5(sel, row, pstr, pstr2, data, minValue, maxValue, callback) lcd_implementation_drawmenu_setting_edit_generic(sel, row, pstr, '>', ftostr5(*(data)))
 #define lcd_implementation_drawmenu_setting_edit_callback_bool(sel, row, pstr, pstr2, data, callback) lcd_implementation_drawmenu_setting_edit_generic_P(sel, row, pstr, '>', (*(data))?PSTR(MSG_ON):PSTR(MSG_OFF))
 
-void lcd_implementation_drawedit(const char* pstr, char* value) {
+void lcd_implementation_drawedit(const char* pstr, const char* value) {
   lcd.setCursor(1, 1);
   lcd_printPGM(pstr);
   lcd.print(':');