Add ctermid.

Change-Id: I7c7c815c2725df222932db923632c8b6419741ab
diff --git a/libc/libc.x86.brillo.map b/libc/libc.x86.brillo.map
index 1a254ae..81b13d0 100644
--- a/libc/libc.x86.brillo.map
+++ b/libc/libc.x86.brillo.map
@@ -1253,6 +1253,7 @@
     catclose;
     catgets;
     catopen;
+    ctermid;
     endgrent;
     endpwent;
     futimes;