rules.pl: Fix creating rules for location based groups.

rules.pl: Fix creating rules for location based groups.

The former used hash value only contains the country code when
a rule for a single country should be created.

In case a location group is used the hash value refers to the group name,
which does not work here.

The required country code is part of the processed string and can be omitted
from here. This works well for single codes and location groups, because those
are processed in a loop.

Fixes #12809.

Signed-off-by: Stefan Schantl <stefan.schantl@ipfire.org>
Acked-by: Peter Müller <peter.mueller@ipfire.org>