sys/socket.h: add SOL_TLS from linux v4.13

socket option for kernel TLS support
new in linux commit 3c4d7559159bfe1e3b94df3a657b2cda3a34e218

include/sys/socket.h

@@ -263,6 +263,7 @@ struct linger {
 #define SOL_ALG         279
 #define SOL_NFC         280
 #define SOL_KCM         281
+#define SOL_TLS         282
 
 #define SOMAXCONN       128