sunxi: Add DRAM_SUN8I_A83T kconfig entry

Add proper and simple kconfig option for dram_sun8i_a83t.c
instead of using MACH type on Makefile.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
diff --git a/arch/arm/mach-sunxi/Kconfig b/arch/arm/mach-sunxi/Kconfig
index 4646684..b868f0e 100644
--- a/arch/arm/mach-sunxi/Kconfig
+++ b/arch/arm/mach-sunxi/Kconfig
@@ -30,6 +30,12 @@
 	  Select this dram controller driver for Sun8i platforms,
 	  for A33 SOC.
 
+config DRAM_SUN8I_A83T
+	bool
+	help
+	  Select this dram controller driver for Sun8i platforms,
+	  for A83T SOC.
+
 config DRAM_SUN9I
 	bool
 	help
@@ -196,6 +202,7 @@
 config MACH_SUN8I_A83T
 	bool "sun8i (Allwinner A83T)"
 	select CPU_V7
+	select DRAM_SUN8I_A83T
 	select SUNXI_GEN_SUN6I
 	select MMC_SUNXI_HAS_NEW_MODE
 	select SUPPORT_SPL