bnx2: avoid compiler warnings

drivers/net/bnx2.c: In function ‘bnx2_enable_forced_2g5’:
drivers/net/bnx2.c:1447: warning: ‘bmcr’ may be used uninitialized in this function
drivers/net/bnx2.c: In function ‘bnx2_disable_forced_2g5’:
drivers/net/bnx2.c:1482: warning: ‘bmcr’ may be used uninitialized in this function

One fix would be to have an initial value, but a plain return might be better.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bnx2.c

@@ -1466,6 +1466,8 @@ bnx2_enable_forced_2g5(struct bnx2 *bp)
 	} else if (CHIP_NUM(bp) == CHIP_NUM_5708) {
 		bnx2_read_phy(bp, bp->mii_bmcr, &bmcr);
 		bmcr |= BCM5708S_BMCR_FORCE_2500;
+	} else {
+		return;
 	}
 
 	if (bp->autoneg & AUTONEG_SPEED) {
@@ -1500,6 +1502,8 @@ bnx2_disable_forced_2g5(struct bnx2 *bp)
 	} else if (CHIP_NUM(bp) == CHIP_NUM_5708) {
 		bnx2_read_phy(bp, bp->mii_bmcr, &bmcr);
 		bmcr &= ~BCM5708S_BMCR_FORCE_2500;
+	} else {
+		return;
 	}
 
 	if (bp->autoneg & AUTONEG_SPEED)