ARM: SAMSUNG: pm: Adjust for pinctrl- and DT-enabled platforms

This patch makes legacy code on suspend/resume path being executed
conditionally, on non-DT platforms only, to fix suspend/resume of
DT-enabled systems, for which the code is inappropriate.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
[olof: add #include <linux/of.h>]
Signed-off-by: Olof Johansson <olof@lixom.net>