iwlwifi: acpi: fill in WGDS table with defaults

The tables we store are the larger of all the revisions, so we need to
fill in the values that we don't get from ACPI when using older
revisions.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210819183728.01b12461a30b.I08d1f9154f26eca25c44616efdb5223bcc1935f3@changeid
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>