clean up warnings

Change-Id: I5421ab90234278920e6080599bb40ffcb3eaa04d

rocclr/os/os_posix.cpp

@@ -372,7 +372,7 @@ const void* Os::createOsThread(amd::Thread* thread) {
   cpu_set_t cpuset;
   if (processorCount_ > 0) {
     CPU_ZERO(&cpuset);
-    for (uint i = 0; i < processorCount_; i++) {
+    for (int i = 0; i < processorCount_; i++) {
       CPU_SET(i, &cpuset);
     }
     if (0 != pthread_attr_setaffinity_np(&threadAttr, sizeof(cpu_set_t), &cpuset)) {