tg3: Support 4mb flash sizes for 5717 and 5719

If a 5717 or 5719 NVRAM part is manually strapped and is 2mb in size,
the driver needs to look at the NVRAM size field rather than infer it
from the strapping itself.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/tg3.c

@@ -11866,6 +11866,8 @@ static void __devinit tg3_get_5717_nvram_info(struct tg3 *tp)
 
 		switch (nvcfg1 & NVRAM_CFG1_5752VENDOR_MASK) {
 		case FLASH_5717VENDOR_ATMEL_MDB021D:
+			/* Detect size with tg3_nvram_get_size() */
+			break;
 		case FLASH_5717VENDOR_ATMEL_ADB021B:
 		case FLASH_5717VENDOR_ATMEL_ADB021D:
 			tp->nvram_size = TG3_NVRAM_SIZE_256KB;
@@ -11891,8 +11893,10 @@ static void __devinit tg3_get_5717_nvram_info(struct tg3 *tp)
 
 		switch (nvcfg1 & NVRAM_CFG1_5752VENDOR_MASK) {
 		case FLASH_5717VENDOR_ST_M_M25PE20:
-		case FLASH_5717VENDOR_ST_A_M25PE20:
 		case FLASH_5717VENDOR_ST_M_M45PE20:
+			/* Detect size with tg3_nvram_get_size() */
+			break;
+		case FLASH_5717VENDOR_ST_A_M25PE20:
 		case FLASH_5717VENDOR_ST_A_M45PE20:
 			tp->nvram_size = TG3_NVRAM_SIZE_256KB;
 			break;