Use MARLIN_EEPROM_SIZE with E2END as fallback (#18059)

Marlin/src/HAL/SAMD51/eeprom_wired.cpp

@@ -32,13 +32,13 @@
 #include "../shared/eeprom_if.h"
 #include "../shared/eeprom_api.h"
 
-size_t PersistentStore::capacity()    { return E2END + 1; }
-bool PersistentStore::access_finish() { return true; }
+#ifndef MARLIN_EEPROM_SIZE
+  #error "MARLIN_EEPROM_SIZE is required for I2C / SPI EEPROM."
+#endif
+size_t PersistentStore::capacity()    { return MARLIN_EEPROM_SIZE; }
 
-bool PersistentStore::access_start() {
-  eeprom_init();
-  return true;
-}
+bool PersistentStore::access_start()  { eeprom_init(); return true; }
+bool PersistentStore::access_finish() { return true; }
 
 bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
   while (size--) {