Fix CardReader string args

Marlin/src/sd/cardreader.cpp

   TERN_(SD_RESORT, if (re_sort) presort());
 }
 
-void CardReader::openLogFile(char * const path) {
+void CardReader::openLogFile(const char * const path) {
   flag.logging = DISABLED(SDCARD_READONLY);
   IF_DISABLED(SDCARD_READONLY, openFileWrite(path));
 }
 //
 // Open a file by DOS path for write
 //
-void CardReader::openFileWrite(char * const path) {
+void CardReader::openFileWrite(const char * const path) {
   if (!isMounted()) return;
 
   announceOpen(2, path);
     SERIAL_ECHOLNPGM(STR_SD_NOT_PRINTING);
 }
 
-void CardReader::write_command(char * const buf) {
+void CardReader::write_command(const char * const buf) {
   char *begin = buf;
   char *npos = nullptr;
   char *end = buf + strlen(buf) - 1;

Marlin/src/sd/cardreader.h

   static void manage_media();
 
   // SD Card Logging
-  static void openLogFile(char * const path);
-  static void write_command(char * const buf);
+  static void openLogFile(const char * const path);
+  static void write_command(const char * const buf);
 
   #if DISABLED(NO_SD_AUTOSTART)     // Auto-Start auto#.g file handling
     static uint8_t autofile_index;  // Next auto#.g index to run, plus one. Ignored by autofile_check when zero.
 
   // Basic file ops
   static void openFileRead(char * const path, const uint8_t subcall=0);
-  static void openFileWrite(char * const path);
+  static void openFileWrite(const char * const path);
   static void closefile(const bool store_location=false);
   static bool fileExists(const char * const name);
   static void removeFile(const char * const name);