autotest: Fix network_WiFiMatFunc/011CheckIBSS

This still doesn't pass on Snow, but at least it fails for a reason
other than undefined variables.

BUG=None
TEST=Test runs, even if not successfully.

Change-Id: I3d5bbab10ffc95244a7df3e6347349b225c13101
Reviewed-on: https://gerrit.chromium.org/gerrit/48466
Tested-by: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Paul Stewart <pstew@chromium.org>
Commit-Queue: Christopher Wiley <wiley@chromium.org>
diff --git a/server/site_linux_router.py b/server/site_linux_router.py
index 71a5d65..d640015 100644
--- a/server/site_linux_router.py
+++ b/server/site_linux_router.py
@@ -540,6 +540,8 @@
 #               self.router.run("rm -f %(log_file)s %(conf_file)s" % instance)
             self.hostapd['log_count'] += 1
         if self.station['configured']:
+            local_servers = self.local_servers
+            self.local_servers = []
             if self.station['type'] == 'ibss':
                 self.router.run("%s dev %s ibss leave" %
                                 (self.cmd_iw, self.station['interface']))