ARM: OMAP5 / DRA7: PM: Provide a dummy startup function for CPU hotplug

ARM: OMAP5 / DRA7: PM: Provide a dummy startup function for CPU hotplug

Dont assume that all OMAP4+ code will be able to use OMAP4 hotplug
logic. On OMAP5, DRA7, we do not need this in place yet, also,
currently the CPU startup pointer is located in omap4_cpu_pm_info
instead of cpu_pm_ops.

So, isolate the function to hotplug_restart pointer in cpu_pm_ops
where it should have belonged, initalize them as per valid startup
pointers for OMAP4430/60 as in current logic, however provide
dummy_cpu_resume to be the startup location as well.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[nm@ti.com: split this out of original code and isolate it]
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>