Fix 1.2 compatibility

Fix 1.2 compatibility

getopt must be executed outside of the get_api5_arguments function,
because there $@ will be overridden.

vol_id may return an error on old distributions (dapper) in that case we
just... err... well... ignore the error and forget to set up the swap
partition in fstab?? :)

Reviewed-by: iustinp