ARM: EXYNOS: Fix crash on soft reset on EXYNOS5440

ARM: EXYNOS: Fix crash on soft reset on EXYNOS5440

commit 60db7e5f9c9a25a7a9b01007e6e3f5a93bc16a3a upstream.

The soft-reset control register is located in the XMU controller space.
Map this controller space before writing to the soft-reset controller
register.

Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Girish K S <ks.giri@samsung.com>
Signed-off-by: Kukjin <kgene.kim@samsung.com>
Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>