wifi: iwlwifi: use correct function to read STEP_URM register

CNVI_PMU_STEP_FLOW is a PRPH register, not a UMAC PRPH register.
Use iwl_read_prph() instead of iwl_read_umac_prph() to read it
correctly.

Signed-off-by: Moriya Itzchaki <moriya.itzchaki@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Link: https://patch.msgid.link/20260515151352.3a69fa2dbda7.I8d96635a9c06a835b05a10b6d66c8a9299676246@changeid
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>

Author: mitzchak

drivers/net/wireless/intel/iwlwifi/pcie/gen1_2/trans-gen2.c

@@ -398,9 +398,9 @@ void iwl_trans_pcie_gen2_fw_alive(struct iwl_trans *trans)
 	mutex_unlock(&trans_pcie->mutex);
 
 	if (trans->mac_cfg->device_family >= IWL_DEVICE_FAMILY_BZ)
-		trans->step_urm = !!(iwl_read_umac_prph(trans,
-							CNVI_PMU_STEP_FLOW) &
-					CNVI_PMU_STEP_FLOW_FORCE_URM);
+		trans->step_urm = !!(iwl_read_prph(trans,
+						   CNVI_PMU_STEP_FLOW) &
+				     CNVI_PMU_STEP_FLOW_FORCE_URM);
 }
 
 static bool iwl_pcie_set_ltr(struct iwl_trans *trans)