ARM: SAMSUNG: Remove remaining legacy code

After refactoring suspend/resume, which was last part with dependencies
on legacy code, all Kconfig symbols related to Samsung ATAGS support can
be deselected and more unused code removed. This includes most of s5p-*
code as well, as s5pv210 was their last user.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>