Fix missing negative flags in netdb.h, add NI_MAXHOST and NI_MAXSERV

include/bits/netdb.h

 #ifndef _BITS_NETDB_H
 #define _BITS_NETDB_H
 
+#define EAI_BADFLAGS (-1)
+#define EAI_NONAME (-2)
+#define EAI_AGAIN (-3)
+#define EAI_FAIL (-4)
+#define EAI_NODATA (-5)
+#define EAI_FAMILY (-6)
+#define EAI_SOCKTYPE (-7)
+#define EAI_SERVICE (-8)
+#define EAI_ADDRFAMILY (-9)
+#define EAI_MEMORY (-10)
+#define EAI_SYSTEM (-11)
+#define EAI_OVERFLOW (-12)
+
 # define        h_addr  h_addr_list[0] /* Address, for backward compatibility.*/
 
 #endif /* _BITS_NETDB_H */

src/header/netdb/mod.rs

@@ -117,6 +117,9 @@ pub const EAI_MEMORY: c_int = -10;
 pub const EAI_SYSTEM: c_int = -11;
 pub const EAI_OVERFLOW: c_int = -12;
 
+pub const NI_MAXHOST: c_int = 1025;
+pub const NI_MAXSERV: c_int = 32;
+
 pub const NI_NUMERICHOST: c_int = 0x0001;
 pub const NI_NUMERICSERV: c_int = 0x0002;
 pub const NI_NOFQDN: c_int = 0x0004;