samsung: exynos: Convert SROMC interface to a driver

Add a bus driver for this and use it to configure the bus parameters for
the Ethernet interface. Drop the old pre-driver-model code.

Switch over to use driver model for Ethernet.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/board/samsung/common/Makefile b/board/samsung/common/Makefile
index 3593c77..d31b81a 100644
--- a/board/samsung/common/Makefile
+++ b/board/samsung/common/Makefile
@@ -7,7 +7,7 @@
 obj-$(CONFIG_MISC_COMMON) += misc.o
 
 ifndef CONFIG_SPL_BUILD
-obj-$(CONFIG_BOARD_COMMON)	+= board.o
+obj-$(CONFIG_BOARD_COMMON)	+= board.o sromc.o
 ifdef CONFIG_EXYNOS5_DT
 obj-y += exynos5-dt.o
 obj-$(CONFIG_BOARD_TYPES) += exynos5-dt-types.o