[PowerProfiler] Make sure correct version of pySerial is imported with monsoon profiler.

tools/telemetry/telemetry/core/util.py

Index: tools/telemetry/telemetry/core/util.py
diff --git a/tools/telemetry/telemetry/core/util.py b/tools/telemetry/telemetry/core/util.py
index efeab5aa7f8eaf6af6e20741002397a34ea5411d..e5114693686f8534025a9fa45077c9940ddf52fb 100644
--- a/tools/telemetry/telemetry/core/util.py
+++ b/tools/telemetry/telemetry/core/util.py
@@ -38,8 +38,10 @@ def GetChromiumSrcDir():
 
 def AddDirToPythonPath(*path_parts):
   path = os.path.abspath(os.path.join(*path_parts))
-  if os.path.isdir(path) and path not in sys.path:
-    sys.path.append(path)
+  if os.path.isdir(path):
+    if path in sys.path:
+      sys.path.remove(path)
+    sys.path.insert(0, path)
 
 _counter = [0]
 def _GetUniqueModuleName():