pthread_yield -> sched_yield
---
--- a/opencl/test/unit_test/os_interface/linux/drm_gem_close_worker_tests.cpp
+++ b/opencl/test/unit_test/os_interface/linux/drm_gem_close_worker_tests.cpp
@@ -121,7 +121,7 @@
 
     //wait for worker to complete or deadCnt drops
     while (!worker->isEmpty() && (deadCnt-- > 0))
-        pthread_yield(); //yield to another threads
+        sched_yield(); //yield to another threads
 
     worker->close(false);
 
@@ -142,7 +142,7 @@
 
     //wait for worker to complete or deadCnt drops
     while (!worker->isEmpty() && (deadCnt-- > 0))
-        pthread_yield(); //yield to another threads
+        sched_yield(); //yield to another threads
 
     //and check if GEM was closed
     EXPECT_EQ(1, this->drmMock->gem_close_cnt.load());