Return back EAI_ADDRFAMILY definition needed for libnl-2.0

Change-Id: I86e6ca8ad92da7a81ea4b659dd9fc9be2d6fd3c9
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
diff --git a/libc/include/netdb.h b/libc/include/netdb.h
index c2e08ea..eb2d99f 100644
--- a/libc/include/netdb.h
+++ b/libc/include/netdb.h
@@ -137,10 +137,7 @@
 /*
  * Error return codes from getaddrinfo()
  */
-#if 0
-/* obsoleted */
 #define	EAI_ADDRFAMILY	 1	/* address family for hostname not supported */
-#endif
 #define	EAI_AGAIN	 2	/* temporary failure in name resolution */
 #define	EAI_BADFLAGS	 3	/* invalid value for ai_flags */
 #define	EAI_FAIL	 4	/* non-recoverable failure in name resolution */