Separate between ini and legacy dump flows to allow adding ini triggers
that are not supported in the legacy flow and to increase readabilty.

iwl_fw_dbg_ini_collect function is now called with legacy trigger id and
_iwl_fw_dbg_ini_collect is called with ini trigger id.

Also make the actual dumping function static so that any dump collection
will go through iwl_fw_dbg_collect_sync.
Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>