ARM: S5PV210: Add DMC map_desc table for supporting DMC access

This patch adds DMC(DRAM Memory Controller) map_desc table.
Because some driver such as CPUFREQ need to access DMC register.

Signed-off-by: Jaecheol Lee <jc.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>