ARM: mvebu: Staticize armada_370_xp_cpu_pm_init

ARM: mvebu: Staticize armada_370_xp_cpu_pm_init

'armada_370_xp_cpu_pm_init' is local to this file.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Link: https://lkml.kernel.org/r/1403610235-22654-3-git-send-email-sachin.kamat@samsung.com
Signed-off-by: Sachin Kamat <sachin.kamat@samsung.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>