Add include guards to some headers

Marlin/src/HAL/HAL_LPC1768/u8g/HAL_LCD_I2C_routines.h

@@ -19,6 +19,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#pragma once
 
 void u8g_i2c_init(uint8_t options);
 uint8_t u8g_i2c_wait(uint8_t mask, uint8_t pos);

Marlin/src/HAL/HAL_LPC1768/u8g/HAL_LCD_defines.h

@@ -19,6 +19,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#pragma once
 
 /**
  * LPC1768 LCD-specific defines

Marlin/src/HAL/HAL_LPC1768/u8g/HAL_LCD_delay.h

@@ -19,6 +19,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#pragma once
 
 /**
  * LCD delay routines - used by all the drivers.

Marlin/src/HAL/HAL_LPC1768/u8g/HAL_LCD_pin_routines.h

@@ -19,6 +19,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#pragma once
 
 /**
  * Low level pin manipulation routines - used by all the drivers.