menu: Fix warnings, clean code

menu: Fix warnings, clean code

This patch adds default values and removes a missing translation
to fix "uninitialized value" and "odd number of elements" warnings.

Removes function calls from functions.pl that have already been
handled by the header before it is loaded by eval().

Signed-off-by: Leo-Andres Hofmann <hofmann@leo-andres.de>
Reviewed-by: Bernhard Bitsch <bbitsch@ipfire.org>