src/udev/udev-rules.c: fix bug introduced in our 601c4e8

This error was introduced in our commit

    601c4e8ce69338652b3c9178386cbc05de8bae8d

when importing from upstream.  The revert line works only
in the context of all of upstream's commit

    7850b3b83791ba0e2377ba40383c5abc258b839d

Signed-off-by: Anthony G. Basile <blueness@gentoo.org>