auototest(wifi): Add a debug log to print reg domain

Add a debug log to print out the current regulatory domain set on the
device after dumping out the iw info.

BUG=b:31219242
TEST=`./site_utils/test_droid.py -r
android1758-row1-rack6-test-station-7.cros -s 00b290db569aa1b7
f:.*network_WiFi_SimpleConnect/control.wifi_check5HT20` and verified
logs.

Change-Id: I3f7599b24f30656586cefd8f550a5abdd176c1e3
Reviewed-on: https://chromium-review.googlesource.com/383018
Commit-Ready: Roshan Pius <rpius@chromium.org>
Tested-by: Roshan Pius <rpius@chromium.org>
Reviewed-by: Bindu Mahadev <bmahadev@chromium.org>
diff --git a/server/site_linux_system.py b/server/site_linux_system.py
index cdb9f12..8192a1e 100644
--- a/server/site_linux_system.py
+++ b/server/site_linux_system.py
@@ -93,6 +93,8 @@
 
         self._phy_list = None
         self.phys_for_frequency, self.phy_bus_type = self._get_phy_info()
+        logging.debug('Current regulatory domain %r',
+                      self.iw_runner.get_regulatory_domain())
         self._interfaces = []
         for interface in self.iw_runner.list_interfaces():
             if self.inherit_interfaces: