net: fix ks8851 build errors

Fix build errors due to missing Kconfig select of CRC32:

ks8851.c:(.text+0x7d2ee): undefined reference to `crc32_le'
ks8851.c:(.text+0x7d2f5): undefined reference to `bitrev32'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/Kconfig

@@ -1733,6 +1733,7 @@ config KS8851
        tristate "Micrel KS8851 SPI"
        depends on SPI
        select MII
+	select CRC32
        help
          SPI driver for Micrel KS8851 SPI attached network chip.