Add NI_* constants

src/unix/redox/mod.rs

@@ -440,6 +440,13 @@ pub const O_NOFOLLOW: ::c_int = -0x8000_0000;
 
 // netdb.h
 pub const EAI_SYSTEM: ::c_int = -11;
+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;
+pub const NI_NAMEREQD: ::c_int = 0x0008;
+pub const NI_DGRAM: ::c_int = 0x0010;
 
 // netinet/in.h
 // FIXME: relibc {