ARM: S5PV210: Place the common SPARSEMEM at ARCH_S5PV210

In case of S5PV210/S5PC110, it uses the SPARSEMEM as default memory
configuration. So moved to ARCH_S5PV210 config.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
[kgene.kim@samsung.com: edited title]
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>