ARM: socfpga: dts: rename socdk board file to socdk_sdmmc

Rename the socfpga_arria10_socdk board file to socfpga_arria10_socdk_sdmmc
as Arria 10 devkit cannot support SDMMC and QSPI at the same time. Thus
we will need to have 2 separate board files, one for SDMMC and one for
QSPI. We also add a new base board dtsi file, socfpga_arria10_socdk.dtsi
so that we use common peripherals for each flavor of the devkits.

Add the sdmmc node to the socfpga_arria10_socdk_sdmmc.dts board file.

Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
index 86217db..2ce74f1 100644
--- a/arch/arm/boot/dts/Makefile
+++ b/arch/arm/boot/dts/Makefile
@@ -496,7 +496,7 @@
 	sh73a0-kzm9g.dtb
 dtb-$(CONFIG_ARCH_SOCFPGA) += \
 	socfpga_arria5_socdk.dtb \
-	socfpga_arria10_socdk.dtb \
+	socfpga_arria10_socdk_sdmmc.dtb \
 	socfpga_cyclone5_socdk.dtb \
 	socfpga_cyclone5_sockit.dtb \
 	socfpga_cyclone5_socrates.dtb \