udev: rules - print the first invalid character
The current code would print the character following the first invalid
character.
Given an udev rules-file without a trailing newline we would otherwise print
garbage:
invalid key/value pair in file /usr/lib/udev/rules.d/40-usb-media-players.rules
on line 26, starting at character 25 ('m')
This is now changed to print
invalid key/value pair in file /usr/lib/udev/rules.d/40-usb-media-players.rules
on line 26, starting at character 25 ('')
(still not very good as printing \0 just gives the empty string)