Fixes typo in platform.h
diff --git a/include/mbedtls/platform.h b/include/mbedtls/platform.h
index f71f1b6..bdf771c 100644
--- a/include/mbedtls/platform.h
+++ b/include/mbedtls/platform.h
@@ -64,7 +64,7 @@
#define MBEDTLS_PLATFORM_STD_FREE free /**< Default free to use */
#endif
#if !defined(MBEDTLS_PLATFORM_STD_EXIT)
-#define MBEDTLS_PLATFORM_STD_EXIT exit /**< Default free to use */
+#define MBEDTLS_PLATFORM_STD_EXIT exit /**< Default exit to use */
#endif
#else /* MBEDTLS_PLATFORM_NO_STD_FUNCTIONS */
#if defined(MBEDTLS_PLATFORM_STD_MEM_HDR)