Fix compiler warning regarding failsafeIndicator

lib/main/CMSIS/CM3/DeviceSupport/ST/STM32F10x/stm32f10x.h

@@ -15,15 +15,15 @@
   *          is using in the C source code, usually in main.c. This file contains:
   *           - Configuration section that allows to select:
   *              - The 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<EFBFBD>s drivers in application code(i.e. 
+  *                code will be based on direct access to peripheral<EFBFBD>s registers 
   *                rather than drivers API), this option is controlled by 
   *                "#define USE_STDPERIPH_DRIVER"
   *              - To change few application-specific parameters such as the HSE 
   *                crystal frequency
   *           - Data structures and the address mapping for all peripherals
   *           - Peripheral's registers declarations and bits definition
-  *           - Macros to access peripheral’s registers hardware
+  *           - Macros to access peripheral<EFBFBD>s registers hardware
   *
   ******************************************************************************
   * @attention

src/main/io/display.c

@@ -212,7 +212,7 @@ void updateRxStatus(void)
 
 void updateFailsafeStatus(void)
 {
-    char failsafeIndicator;
+    char failsafeIndicator = '?';
     switch (failsafePhase()) {
         case FAILSAFE_IDLE:
             failsafeIndicator = '-';