Fix time out

When there are lots of virtual network interfaces `ntpq` is somehow confused and returns this error:
> localhost: timed out, nothing received
> ***Request timed out CheckNTP UNKNOWN: NTP command Failed

Defining 127.0.0.1 host at end of `ntpq` command fixed this problem.

bin/check-ntp.rb

@@ -59,10 +59,10 @@ class CheckNTP < Sensu::Plugin::Check::CLI
 
   def run
     begin
-      output = `ntpq -c "rv 0 stratum,offset"`.split("\n").find { |line| line.start_with?('stratum') }
+      output = `ntpq -c "rv 0 stratum,offset" 127.0.0.1`.split("\n").find { |line| line.start_with?('stratum') }
       stratum = output.split(',')[0].split('=')[1].strip.to_i
       offset = output.split(',')[1].split('=')[1].strip.to_f
-      source_field_status = config[:unsynced_status] == 'ok' ? 6 : /status=[0-9a-f]([0-9])[0-9a-f]{2}/.match(`ntpq -c "rv 0"`)[1].to_i
+      source_field_status = config[:unsynced_status] == 'ok' ? 6 : /status=[0-9a-f]([0-9])[0-9a-f]{2}/.match(`ntpq -c "rv 0" 127.0.0.1`)[1].to_i
     rescue
       unknown 'NTP command Failed'
     end