UPSTREAM: clk: rockchip: release io resource when failing to init clk

UPSTREAM: clk: rockchip: release io resource when failing to init clk

We should call iounmap to relase reg_base since it's not going
to be used any more if failing to init clk.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
(cherry picked from git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip.git
v4.8-clk/next commit 1d003eb0805ac5b549e76202a1e95da33f62cb9a)

Change-Id: Ia0161885786d6504fee7e76c6620df98bb2cdb21
Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>