iwlwifi: dbg: support multiple dumps in legacy dump flow

Support multiple debug data collection triggers in legacy flow.
Utilize the already existing Yoyo infra so the change is rather simple.

Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200417131727.5be6a1923cbe.I10701236b03f66328041f2a38f5f0f22a26fd40b@changeid

drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c

@@ -1264,7 +1264,6 @@ static void iwl_mvm_mac_stop(struct ieee80211_hw *hw)
 
 	cancel_delayed_work_sync(&mvm->cs_tx_unblock_dwork);
 	cancel_delayed_work_sync(&mvm->scan_timeout_dwork);
-	iwl_fw_free_dump_desc(&mvm->fwrt);
 
 	mutex_lock(&mvm->mutex);
 	__iwl_mvm_mac_stop(mvm);