Add units to time periods

Change-Id: Ib980e2676cecf5d9b0c2e388da6dc8e370df8abb
diff --git a/services/audioflinger/AudioPolicyService.cpp b/services/audioflinger/AudioPolicyService.cpp
index fcf014f..b4da4a1 100644
--- a/services/audioflinger/AudioPolicyService.cpp
+++ b/services/audioflinger/AudioPolicyService.cpp
@@ -47,7 +47,7 @@
 static const char *kCmdDeadlockedString = "AudioPolicyService command thread may be deadlocked\n";
 
 static const int kDumpLockRetries = 50;
-static const int kDumpLockSleep = 20000;
+static const int kDumpLockSleepUs = 20000;
 
 static bool checkPermission() {
     if (getpid() == IPCThreadState::self()->getCallingPid()) return true;
@@ -563,7 +563,7 @@
             locked = true;
             break;
         }
-        usleep(kDumpLockSleep);
+        usleep(kDumpLockSleepUs);
     }
     return locked;
 }