i40e: Make i40e_shutdown_adminq() return void

Fix the following coccicheck warning:

drivers/net/ethernet/intel/i40e/i40e_adminq.c:699:13-21: Unneeded
variable: "ret_code". Return "0" on line 710
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_adminq.c

@@ -694,10 +694,8 @@ i40e_status i40e_init_adminq(struct i40e_hw *hw)
  *  i40e_shutdown_adminq - shutdown routine for the Admin Queue
  *  @hw: pointer to the hardware structure
  **/
-i40e_status i40e_shutdown_adminq(struct i40e_hw *hw)
+void i40e_shutdown_adminq(struct i40e_hw *hw)
 {
-	i40e_status ret_code = 0;
-
 	if (i40e_check_asq_alive(hw))
 		i40e_aq_queue_shutdown(hw, true);
 
@@ -706,8 +704,6 @@ i40e_status i40e_shutdown_adminq(struct i40e_hw *hw)
 
 	if (hw->nvm_buff.va)
 		i40e_free_virt_mem(hw, &hw->nvm_buff);
-
-	return ret_code;
 }
 
 /**

drivers/net/ethernet/intel/i40e/i40e_prototype.h

@@ -17,7 +17,7 @@
 
 /* adminq functions */
 i40e_status i40e_init_adminq(struct i40e_hw *hw);
-i40e_status i40e_shutdown_adminq(struct i40e_hw *hw);
+void i40e_shutdown_adminq(struct i40e_hw *hw);
 void i40e_adminq_init_ring_data(struct i40e_hw *hw);
 i40e_status i40e_clean_arq_element(struct i40e_hw *hw,
 					     struct i40e_arq_event_info *e,