kconfig_lint: Change from '$file at line $line' to $file:$line
Combine the file and line number into a combination that editors
understand when opening files. This makes it easier to edit the
errors.
Change-Id: Id2fae6a0a2ca8d726b95e252d80ac918f4edbe23
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/12561
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>