Do not use pthread_setname_np on GNU/Hurd

This function is not available there.

Bug: aomedia:3306
Change-Id: Ia7e4812d2356728ebf497cb45506e6de0a23d90b
diff --git a/aom_util/aom_thread.c b/aom_util/aom_thread.c
index a749a22..3916021 100644
--- a/aom_util/aom_thread.c
+++ b/aom_util/aom_thread.c
@@ -52,7 +52,7 @@
     thread_name[sizeof(thread_name) - 1] = '\0';
     pthread_setname_np(thread_name);
   }
-#elif defined(__GLIBC__) || defined(__BIONIC__)
+#elif (defined(__GLIBC__) && !defined(__GNU__)) || defined(__BIONIC__)
   if (worker->thread_name != NULL) {
     // Linux and Android require names (with nul) fit in 16 chars, otherwise
     // pthread_setname_np() returns ERANGE (34).