Update version number to 2.1.9
diff --git a/include/mbedtls/version.h b/include/mbedtls/version.h
index 2ffa62c..118130a 100644
--- a/include/mbedtls/version.h
+++ b/include/mbedtls/version.h
@@ -39,16 +39,16 @@
  */
 #define MBEDTLS_VERSION_MAJOR  2
 #define MBEDTLS_VERSION_MINOR  1
-#define MBEDTLS_VERSION_PATCH  8
+#define MBEDTLS_VERSION_PATCH  9
 
 /**
  * The single version number has the following structure:
  *    MMNNPP00
  *    Major version | Minor version | Patch version
  */
-#define MBEDTLS_VERSION_NUMBER         0x02010800
-#define MBEDTLS_VERSION_STRING         "2.1.8"
-#define MBEDTLS_VERSION_STRING_FULL    "mbed TLS 2.1.8"
+#define MBEDTLS_VERSION_NUMBER         0x02010900
+#define MBEDTLS_VERSION_STRING         "2.1.9"
+#define MBEDTLS_VERSION_STRING_FULL    "mbed TLS 2.1.9"
 
 #if defined(MBEDTLS_VERSION_C)