sunxi: provide default DRAM config for sun50i in Kconfig

To avoid enumerating the very same DRAM values in defconfig files
for each and every Allwinner A64 board out there, let's put some sane
default values in the Kconfig file.
Boards with different needs can override them at any time.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>

board/sunxi/Kconfig

@@ -168,6 +168,7 @@ config DRAM_CLK
 	default 792 if MACH_SUN9I
 	default 312 if MACH_SUN6I || MACH_SUN8I
 	default 360 if MACH_SUN4I || MACH_SUN5I || MACH_SUN7I
+	default 672 if MACH_SUN50I
 	---help---
 	Set the dram clock speed, valid range 240 - 480 (prior to sun9i),
 	must be a multiple of 24. For the sun9i (A80), the tested values
@@ -187,6 +188,7 @@ config DRAM_ZQ
 	default 123 if MACH_SUN4I || MACH_SUN5I || MACH_SUN6I || MACH_SUN8I
 	default 127 if MACH_SUN7I
 	default 4145117 if MACH_SUN9I
+	default 3881915 if MACH_SUN50I
 	---help---
 	Set the dram zq value.
 

configs/pine64_plus_defconfig

@@ -2,8 +2,6 @@ CONFIG_ARM=y
 CONFIG_RESERVE_ALLWINNER_BOOT0_HEADER=y
 CONFIG_ARCH_SUNXI=y
 CONFIG_MACH_SUN50I=y
-CONFIG_DRAM_CLK=672
-CONFIG_DRAM_ZQ=3881915
 CONFIG_DEFAULT_DEVICE_TREE="sun50i-a64-pine64-plus"
 # CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
 CONFIG_CONSOLE_MUX=y