Remove deprecated getaddrinfo() flags

AI_IDN_ALLOW_UNASSIGNED and AI_IDN_USE_STD3_ASCII_RULES flags are
deprecated by glibc-2.28 and the deprecation warnings did cause fail of
Debug build, because of -Werror.

Fixes #3766.

src/lua/socket.c

@@ -391,12 +391,6 @@ static const struct { char name[32]; int value; } ai_flags[] = {
 #ifdef AI_CANONIDN
 	{"AI_CANONIDN",			AI_CANONIDN			},
 #endif
-#ifdef AI_IDN_ALLOW_UNASSIGNED
-	{"AI_IDN_ALLOW_UNASSIGNED",	AI_IDN_ALLOW_UNASSIGNED		},
-#endif
-#ifdef AI_IDN_USE_STD3_ASCII_RULES
-	{"AI_IDN_USE_STD3_ASCII_RULES",	AI_IDN_USE_STD3_ASCII_RULES	},
-#endif
 #ifdef AI_NUMERICSERV
 	{"AI_NUMERICSERV",		AI_NUMERICSERV			},
 #endif