e1000e: cleanup: always return 0

These are a few instances of returning a value that can only be 0 so just
use a 'return 0' to make it more obvious.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/e1000e/82571.c b/drivers/net/ethernet/intel/e1000e/82571.c
index 024ac24..05e9a291 100644
--- a/drivers/net/ethernet/intel/e1000e/82571.c
+++ b/drivers/net/ethernet/intel/e1000e/82571.c
@@ -796,7 +796,7 @@
 	 * otherwise, commit the checksum to the flash NVM.
 	 */
 	if (hw->nvm.type != e1000_nvm_flash_hw)
-		return ret_val;
+		return 0;
 
 	/* Check for pending operations. */
 	for (i = 0; i < E1000_FLASH_UPDATES; i++) {