fix byte 0x92 (#19)

Author: bongbui321

board/inc/stm32f4xx.h

@@ -8,8 +8,8 @@
   *          is using in the C source code, usually in main.c. This file contains:
   *           - Configuration section that allows to select:
   *              - The STM32F4xx device used in the target application
-  *              - To use or not the peripheral’s drivers in application code(i.e. 
-  *                code will be based on direct access to peripheral’s registers 
+  *              - To use or not the peripheral's drivers in application code(i.e. 
+  *                code will be based on direct access to peripheral's registers 
   *                rather than drivers API), this option is controlled by 
   *                "#define USE_HAL_DRIVER"
   *