sun6i: Make dram clk and zq value Kconfig options

It turns out that there is a too large spread between boards to handle this
with a default value, turn this into Kconfig options, and set the values
the factory images are using for the Colombus and Mele_M9 boards.

Note this changes the ZQ default when not overriden through defconfig from
120 to 123, as that is what most boards seem to actually use.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
diff --git a/configs/Mele_M9_defconfig b/configs/Mele_M9_defconfig
index ac3cd36..a598254 100644
--- a/configs/Mele_M9_defconfig
+++ b/configs/Mele_M9_defconfig
@@ -5,6 +5,8 @@
 +S:CONFIG_ARCH_SUNXI=y
 +S:CONFIG_MACH_SUN6I=y
 +S:CONFIG_TARGET_MELE_M9=y
++S:CONFIG_DRAM_CLK=312
++S:CONFIG_DRAM_ZQ=120
 # Ethernet phy power
 +S:CONFIG_AXP221_DLDO1_VOLT=3300
 # USB hub power