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>

arch/mips/mach-octeon/dram.c

@@ -81,7 +81,7 @@ phys_size_t board_get_usable_ram_top(phys_size_t total_size)
 {
 	if (IS_ENABLED(CONFIG_RAM_OCTEON)) {
 		/* Map a maximum of 256MiB - return not size but address */
-		return CONFIG_SYS_SDRAM_BASE + min(gd->ram_size,
+		return CFG_SYS_SDRAM_BASE + min(gd->ram_size,
 						   UBOOT_RAM_SIZE_MAX);
 	} else {
 		return gd->ram_top;