samsung: Add mmc controller to use dwmmc

This patch set for use dw mmc controller.
Patch enable supporting device tree for dw mmc controller. For use dwmmc controller on trats2 board, enable configuration dw_mmc, exynos_dwmmc, bounce_buffer and then disable sdhci configuration. This patch set tested on TRATS2 board.

Changes for v3:
- Set bank_ext of SDMMC2 for prevent compile warning.
- Subtract one from div to set accurate frequency.

Changes for v2:
- Use device tree for dw mmc controller.
- dw mmc node is added device node on exynos4 device tree.
- dw mmc controller driver is fixed for use exynos4 and 5.
- Add fdt compat id of exynos4 dwmmc.
- Add comment.

Beomho Seo (4):
drivers: mmc: dwmmc: enable support for DT
arm: exynos: pinmux: Add sdmmc4 gpio configuration
arm: exynos: clock: Remove exynos4x12_set_mmc_clk function
board: trats2: Enable device tree on Trats2

 arch/arm/cpu/armv7/exynos/clock.c  |   29 +----------------------------
 arch/arm/cpu/armv7/exynos/pinmux.c |   18 +++++++++++++++---
 arch/arm/dts/exynos4.dtsi          |    8 ++++++++
 arch/arm/dts/exynos4412-trats2.dts |    8 ++++++++
 drivers/mmc/exynos_dw_mmc.c        |   21 +++++++++++++++++----
 include/fdtdec.h                   |    1 +
 lib/fdtdec.c                       |    1 +
 7 files changed, 51 insertions(+), 35 deletions(-)

1.7.9.5