servod: fix bug reporting command line parameters mismatch

There is no need to report a problem if the command line parameter
matches the config file value. But if there is a mismatch, let's use
the servo serial number to identify which servo the message is for.

TEST=passing -b on the command line when the config file is used does
     not cause a failure anymore. If the command line parameter does
     not agree with the config file, a proper message is printed:

     $ grep storm /home/vbendeb/.servodrc
     storm, 686203-00062, 9900, storm
     $ servod -b storm  # succeeds
     $ servod -b daisy
     2015-03-25 13:09:13,877 - - WARNING - Ignoring rc configured board name storm for servo 686203-00062

Change-Id: I92339eed0707decbf5b6b0040437308aca9346fd
Tested-by: Vadim Bendebury <>
Reviewed-by: Todd Broch <>
Commit-Queue: Vadim Bendebury <>
1 file changed