Override for LPC1768 u8g/digipot I2C master ID (#16622)

Marlin/Configuration_adv.h

 
 #endif // HAS_L64XX
 
+// @section i2cbus
+
+//
+// I2C Master ID for LPC176x LCD and Digital Current control
+// Does not apply to other peripherals based on the Wire library.
+//
+//#define I2C_MASTER_ID  1  // Set a value from 0 to 2
+
 /**
  * TWI/I2C BUS
  *
  * echo:i2c-reply: from:99 bytes:5 data:hello
  */
 
-// @section i2cbus
-
 //#define EXPERIMENTAL_I2CBUS
-#define I2C_SLAVE_ADDRESS  0 // Set a value from 8 to 127 to act as a slave
+#if ENABLED(EXPERIMENTAL_I2CBUS)
+  #define I2C_SLAVE_ADDRESS  0  // Set a value from 8 to 127 to act as a slave
+#endif
 
 // @section extras
 

Marlin/src/HAL/HAL_LPC1768/include/i2c_util.c

 
 #ifdef TARGET_LPC1768
 
-#include "../../../inc/MarlinConfigPre.h"
 #include "i2c_util.h"
 
 #define U8G_I2C_OPT_FAST 16  // from u8g.h
   PinCfg.OpenDrain = 0;
   PinCfg.Pinmode = 0;
   PinCfg.Portnum = 0;
-  #if USEDI2CDEV_M == 0
+  #if I2C_MASTER_ID == 0
     PinCfg.Funcnum = 1;
     PinCfg.Pinnum = 27;     // SDA0 / D57  AUX-1 ... SCL0 / D58  AUX-1
-  #elif USEDI2CDEV_M == 1
+  #elif I2C_MASTER_ID == 1
     PinCfg.Funcnum = 3;
     PinCfg.Pinnum = 0;      // SDA1 / D20 SCA ... SCL1 / D21 SCL
-  #elif USEDI2CDEV_M == 2
+  #elif I2C_MASTER_ID == 2
     PinCfg.Funcnum = 2;
     PinCfg.Pinnum = 10;     // SDA2 / D38  X_ENABLE_PIN ... SCL2 / D55  X_DIR_PIN
   #endif

Marlin/src/HAL/HAL_LPC1768/include/i2c_util.h

  * HAL_LPC1768/include/i2c_util.h
  */
 
-#ifndef USEDI2CDEV_M
-  #define USEDI2CDEV_M  1  // By default use I2C1 controller
+#include "../../../inc/MarlinConfigPre.h"
+
+#ifndef I2C_MASTER_ID
+  #define I2C_MASTER_ID 1
 #endif
 
-#if USEDI2CDEV_M == 0
+#if I2C_MASTER_ID == 0
   #define I2CDEV_M LPC_I2C0
-#elif USEDI2CDEV_M == 1
+#elif I2C_MASTER_ID == 1
   #define I2CDEV_M LPC_I2C1
-#elif USEDI2CDEV_M == 2
+#elif I2C_MASTER_ID == 2
   #define I2CDEV_M LPC_I2C2
 #else
   #error "Master I2C device not defined!"

Marlin/src/HAL/HAL_LPC1768/u8g/LCD_I2C_routines.cpp

 
 #ifdef TARGET_LPC1768
 
+#include "../include/i2c_util.h"
+#include "../../../core/millis_t.h"
+
 extern int millis();
 
 #ifdef __cplusplus
   extern "C" {
 #endif
 
-#include "../include/i2c_util.h"
-#include "../../../core/millis_t.h"
-
 //////////////////////////////////////////////////////////////////////////////////////
 
 // These two routines are exact copies of the lpc17xx_i2c.c routines.  Couldn't link to