ARM: S5PV210: Fix regulator names

Since commit 1130e5b3 regulators are exported to debugfs. The names
of the regulators that contains slash ('/') causes an ops during kernel
boot. This patch fixes this issue.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>