Fix style issues

include/mbedtls/platform_util.h

@@ -177,7 +177,7 @@ void mbedtls_platform_zeroize( void *buf, size_t len );
  * \param ptr   Buffer to be set.
  * \param value Value to be used when setting the buffer.
  * \param num   The length of the buffer in bytes.
- * 
+ *
  */
 void mbedtls_platform_memset( void *ptr, int value, size_t num );