iwlwifi: dbg_ini: set dump bit only when trigger collection is certain

In case the the trigger occurrences is zero or force_restart is set, the
driver sets IWL_FWRT_STATUS_DUMPING without actually scheduling trigger
collection. At this point no other dump collection can be performed.

Solve this by setting IWL_FWRT_STATUS_DUMPING bit only when the driver
is surely going to schedule dump collection

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