Add trivial no-op <nl_types.h>.

Needed to build OpenMP.

Bug: http://b/27617302
Change-Id: Iac15c84ead6f5d5274cfdb2d6d4a4ec0072244bb
diff --git a/libc/libc.arm.map b/libc/libc.arm.map
index fa83528..1c7a0ba 100644
--- a/libc/libc.arm.map
+++ b/libc/libc.arm.map
@@ -1273,6 +1273,9 @@
 
 LIBC_O {
   global:
+    catclose;
+    catgets;
+    catopen;
     getdomainname;
     getsubopt;
     hasmntopt;