Quietly check for the _source option
xf86CheckStrOption returns the same value but doesn't mark it as used in the server and, more importantly, doesn't spam the log with
(**) Option "_source" "server/udev"messages.
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xf86CheckStrOption returns the same value but doesn't mark it as used in the server and, more importantly, doesn't spam the log with
(**) Option "_source" "server/udev"messages.