[LIB][EEPROM] Fix error handling in auto init function

Instead of providing a default that may match or not, just fail if the
bus and address for the eeprom is not configured.
Also added a build-time warning.

board/seco/common/seco_eeprom_manager.c

@@ -26,10 +26,12 @@
 */
 
 #ifndef SECO_EEPROM_I2C_BUS
-#define SECO_EEPROM_I2C_BUS                    0x04
+#define SECO_EEPROM_I2C_BUS                    -1
+#warning SECO_EEPROM_I2C_BUS is not specified, please configure it in the board header file.
 #endif
 #ifndef SECO_EEPROM_I2C_ADDR
-#define SECO_EEPROM_I2C_ADDR                   0x50
+#define SECO_EEPROM_I2C_ADDR                   -1
+#warning SECO_EEPROM_I2C_ADDR is not specified, please configure it in the board header file.
 #endif
 
 u8 g_raw_data[EEPROM_SIZE];
@@ -265,9 +267,20 @@ int seco_eeprom_auto_init(void)
 	int i2c_addr = SECO_EEPROM_I2C_ADDR;
 
 	env_str = env_get("seco_eeprom_i2c_bus");
-	if( env_str) i2c_bus_number  = simple_strtoul(env_str, NULL, 0);
+	if( env_str)
+		i2c_bus_number  = simple_strtoul(env_str, NULL, 0);
+	else if(i2c_bus_number < 0){
+		printf( "seco_eeprom_manager: Failed to auto initialize, 'i2c bus number' not found in environment or board header.\n");
+		return -1;
+	}
+
 	env_str = env_get("seco_eeprom_i2c_addr");
-	if( env_str) i2c_addr  = simple_strtoul(env_str, NULL, 0);
+	if( env_str)
+		i2c_addr  = simple_strtoul(env_str, NULL, 0);
+	else if( i2c_addr < 0){
+		printf( "seco_eeprom_manager: Failed to auto initialize, 'i2c address' not found in environment or board header.\n");
+		return -1;
+	}
 
 	return seco_eeprom_init(i2c_bus_number, i2c_addr);
 }