sfc: Use kernel I2C system and i2c-algo-bit driver

Remove our own implementation of I2C bit-banging.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/sfc/Kconfig b/drivers/net/sfc/Kconfig
index dbad95c..3be13b5 100644
--- a/drivers/net/sfc/Kconfig
+++ b/drivers/net/sfc/Kconfig
@@ -4,6 +4,8 @@
 	select MII
 	select INET_LRO
 	select CRC32
+	select I2C
+	select I2C_ALGOBIT
 	help
 	  This driver supports 10-gigabit Ethernet cards based on
 	  the Solarflare Communications Solarstorm SFC4000 controller.