Provide cross platform vsnprintf wrapper
diff --git a/library/version_features.c b/library/version_features.c
index b613546..8cb6d0b 100644
--- a/library/version_features.c
+++ b/library/version_features.c
@@ -72,6 +72,9 @@
 #if defined(MBEDTLS_PLATFORM_SNPRINTF_ALT)
     "MBEDTLS_PLATFORM_SNPRINTF_ALT",
 #endif /* MBEDTLS_PLATFORM_SNPRINTF_ALT */
+#if defined(MBEDTLS_PLATFORM_VSNPRINTF_ALT)
+    "MBEDTLS_PLATFORM_VSNPRINTF_ALT",
+#endif /* MBEDTLS_PLATFORM_VSNPRINTF_ALT */
 #if defined(MBEDTLS_PLATFORM_NV_SEED_ALT)
     "MBEDTLS_PLATFORM_NV_SEED_ALT",
 #endif /* MBEDTLS_PLATFORM_NV_SEED_ALT */