Fix androidGetThreadPriority for non-pthread configurations.

related-to-build

Change-Id: Ic865af0865906f96fd615a56a030c8e3adaf13c4
diff --git a/libs/utils/Threads.cpp b/libs/utils/Threads.cpp
index 38c4b35..5dbcb75 100644
--- a/libs/utils/Threads.cpp
+++ b/libs/utils/Threads.cpp
@@ -369,7 +369,11 @@
 }
 
 int androidGetThreadPriority(pid_t tid) {
+#if defined(HAVE_PTHREADS)
     return getpriority(PRIO_PROCESS, tid);
+#else
+    return ANDROID_PRIORITY_NORMAL;
+#endif
 }
 
 int androidGetThreadSchedulingGroup(pid_t tid)