iwlwifi: dbg_ini: abort region collection in case the size is 0

Allows to abort region collection in case the region size is 0.
It is needed for future regions that their size might be 0.

Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>