i40e: clean up local variable initialization

In both i40e_calc_nvm_checksum() and i40e_update_nvm_checksum(), the
local variables designated by 'ret_code' are overwritten immediately. As
such, they should merely be declared.
Signed-off-by: Jean Sacren <sakiwit@gmail.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_nvm.c

@@ -484,7 +484,7 @@ static i40e_status i40e_write_nvm_aq(struct i40e_hw *hw, u8 module_pointer,
 static i40e_status i40e_calc_nvm_checksum(struct i40e_hw *hw,
 						    u16 *checksum)
 {
-	i40e_status ret_code = 0;
+	i40e_status ret_code;
 	struct i40e_virt_mem vmem;
 	u16 pcie_alt_module = 0;
 	u16 checksum_local = 0;
@@ -564,7 +564,7 @@ static i40e_status i40e_calc_nvm_checksum(struct i40e_hw *hw,
  **/
 i40e_status i40e_update_nvm_checksum(struct i40e_hw *hw)
 {
-	i40e_status ret_code = 0;
+	i40e_status ret_code;
 	u16 checksum;
 	__le16 le_sum;