LogcatMonitor: Fix clear_log
diff --git a/devlib/utils/android.py b/devlib/utils/android.py
index b7c73e6..318b4d0 100644
--- a/devlib/utils/android.py
+++ b/devlib/utils/android.py
@@ -607,7 +607,7 @@
             return [line for line in fh]
 
     def clear_log(self):
-        with open(self._logfile, 'w') as fh:
+        with open(self._logfile.name, 'w') as fh:
             pass
 
     def search(self, regexp):