net: e1000: fix indentation

Apparently the indentation is off here, for the IGB model just want to
bail out early.
Fix this to avoid both compiler warnings and puzzled readers.

Pointed out by GCC 6.2's -Wmisleading-indentation warning.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>

drivers/net/e1000.c

@@ -1522,11 +1522,10 @@ e1000_initialize_hardware_bits(struct e1000_hw *hw)
 		reg_txdctl1 |= E1000_TXDCTL_COUNT_DESC;
 		E1000_WRITE_REG(hw, TXDCTL1, reg_txdctl1);
 
-	/* IGB is cool */
-	if (hw->mac_type == e1000_igb)
-		return;
 
 		switch (hw->mac_type) {
+		case e1000_igb:			/* IGB is cool */
+			return;
 		case e1000_82571:
 		case e1000_82572:
 			/* Clear PHY TX compatible mode bits */