ethoc: fix library build errors

ethoc indirectly uses crc32_le() and bitrev32(), so select
those library functions to be built.

drivers/built-in.o: In function `ethoc_set_multicast_list':
ethoc.c:(.text+0x6226f): undefined reference to `crc32_le'
ethoc.c:(.text+0x62276): 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

@@ -977,6 +977,8 @@ config ETHOC
 	depends on NET_ETHERNET && HAS_IOMEM
 	select MII
 	select PHYLIB
+	select CRC32
+	select BITREVERSE
 	help
 	  Say Y here if you want to use the OpenCores 10/100 Mbps Ethernet MAC.