Autotest: Change logging.warn() to logging.warning().

logging.warn() is deprecated. See
http://bugs.python.org/issue13235

Substitution was performed via
~/cros/src/third_party/autotest/files$ find ./ -type f | xargs sed -i 's/logging.warn(/logging.warning(/'

BUG=None.
TEST=There should be one-- and preferably only one --obvious way to do it.

Change-Id: Ie5665743121a49f7fbd5d1f47896a7c65e87e489
Reviewed-on: https://chromium-review.googlesource.com/198793
Commit-Queue: Ilja Friedel <ihf@chromium.org>
Tested-by: Ilja Friedel <ihf@chromium.org>
Reviewed-by: Alex Miller <milleral@chromium.org>
diff --git a/client/bin/site_utils.py b/client/bin/site_utils.py
index d092e69..1fbd20c 100644
--- a/client/bin/site_utils.py
+++ b/client/bin/site_utils.py
@@ -651,7 +651,7 @@
             temperature = int(line.split(': ')[1]) - 273
             temperatures.append(temperature)
     except Exception:
-        logging.warn('Unable to read temperature sensors using ectool.')
+        logging.warning('Unable to read temperature sensors using ectool.')
     for temperature in temperatures:
         # Sanity check for real world values.
         assert ((temperature > 10.0) and