net: Add SMC911X driver to Kconfig, convert

We add the various SMC91XX symbols to drivers/net/Kconfig and then this
converts the following to Kconfig:
   CONFIG_SMC911X
   CONFIG_SMC911X_BASE
   CONFIG_SMC911X_16_BIT
   CONFIG_SMC911X_32_BIT

Signed-off-by: Adam Ford <aford173@gmail.com>
[trini: Apply to the rest of the tree, re-squash old and new patch]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/vexpress_ca5x2_defconfig b/configs/vexpress_ca5x2_defconfig
index efa8c31..3f8bc9c 100644
--- a/configs/vexpress_ca5x2_defconfig
+++ b/configs/vexpress_ca5x2_defconfig
@@ -18,5 +18,9 @@
 # CONFIG_CMD_MISC is not set
 CONFIG_ENV_IS_IN_FLASH=y
 CONFIG_MTD_NOR_FLASH=y
+CONFIG_NETDEVICES=y
+CONFIG_SMC911X=y
+CONFIG_SMC911X_BASE=0x1a000000
+CONFIG_SMC911X_32_BIT=y
 CONFIG_BAUDRATE=38400
 CONFIG_OF_LIBFDT=y