Temporary apply LIBC version to __pthread_gettid

This is workaround for http://b/26391427

Bug: http://b/26391427
Change-Id: Ibf5c611cf4c04dfa595644225e6d9503089a18da
diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index a91c4d7..4c11ae3 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -123,6 +123,7 @@
     __pselect6; # arm x86 mips
     __pthread_cleanup_pop;
     __pthread_cleanup_push;
+    __pthread_gettid; # arm x86 mips nobrillo
     __ptrace; # arm x86 mips
     __putlong;
     __putshort;