net: tg3: avoid uninitialized variable warning

The tg3_set_eeprom() function correctly initializes the 'start' variable,
but gcc generates a false warning:

drivers/net/ethernet/broadcom/tg3.c: In function 'tg3_set_eeprom':
drivers/net/ethernet/broadcom/tg3.c:12057:4: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized]

I have not come up with a way to restructure the code in a way that
avoids the warning without making it less readable, so this adds an
initialization for the declaration to shut up that warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/tg3.c

@@ -12016,7 +12016,7 @@ static int tg3_set_eeprom(struct net_device *dev, struct ethtool_eeprom *eeprom,
 	int ret;
 	u32 offset, len, b_offset, odd_len;
 	u8 *buf;
-	__be32 start, end;
+	__be32 start = 0, end;
 
 	if (tg3_flag(tp, NO_NVRAM) ||
 	    eeprom->magic != TG3_EEPROM_MAGIC)