global: Move remaining CONFIG_SYS_SDRAM_* to CFG_SYS_SDRAM_*

The rest of the unmigrated CONFIG symbols in the CONFIG_SYS_SDRAM
namespace do not easily transition to Kconfig. In many cases they likely
should come from the device tree instead. Move these out of CONFIG
namespace and in to CFG namespace.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/doc/arch/m68k.rst b/doc/arch/m68k.rst
index 15806df..584503e 100644
--- a/doc/arch/m68k.rst
+++ b/doc/arch/m68k.rst
@@ -142,21 +142,21 @@
   cache-related registers config
 CONFIG_SYS_CACHE_ACRX:
   cache-related registers config
-CONFIG_SYS_SDRAM_BASE:
+CFG_SYS_SDRAM_BASE:
   SDRAM config for SDRAM controller-specific registers
-CONFIG_SYS_SDRAM_SIZE:
+CFG_SYS_SDRAM_SIZE:
   SDRAM config for SDRAM controller-specific registers
-CONFIG_SYS_SDRAM_BASEX:
+CFG_SYS_SDRAM_BASEX:
   SDRAM config for SDRAM controller-specific registers
-CONFIG_SYS_SDRAM_CFG1:
+CFG_SYS_SDRAM_CFG1:
   SDRAM config for SDRAM controller-specific registers
-CONFIG_SYS_SDRAM_CFG2:
+CFG_SYS_SDRAM_CFG2:
   SDRAM config for SDRAM controller-specific registers
-CONFIG_SYS_SDRAM_CTRL:
+CFG_SYS_SDRAM_CTRL:
   SDRAM config for SDRAM controller-specific registers
-CONFIG_SYS_SDRAM_MODE:
+CFG_SYS_SDRAM_MODE:
   SDRAM config for SDRAM controller-specific registers
-CONFIG_SYS_SDRAM_EMOD:
+CFG_SYS_SDRAM_EMOD:
   SDRAM config for SDRAM controller-specific registers, please
   see arch/m68k/cpu/<specific_cpu>/start.S files to see how
   these options are used.