ARM: OMAP2+: Remove suspend_set_ops from common pm late init

In omap2_common_pm_late_init suspend_set_ops was called to set common
suspend handling functions for all omap platforms. This created two
problems. First, these suspend ops were being set for all platforms,
regardless of whether or not suspend support has been integrated so in
the case of AM33XX, suspend to mem was presented as available but
failed every time. Second, some platforms will need to define a
completely separate set of suspend ops, such as AM33XX, due to
differences from previous omap platforms so there is no need to
always set the common omap ops.

This patch moves the suspend_set_ops call from omap2_common_pm_late_init
into a separate function that then gets called in the omap*_pm_init
functions for each platform.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>