soc: ti: Remove pm_runtime_irq_safe() usage for smartreflex

soc: ti: Remove pm_runtime_irq_safe() usage for smartreflex

For the smartreflex device, we need to disable smartreflex on SoC idle,
and have been using pm_runtime_irq_safe() to do that. But we want to
remove the irq_safe usage as PM runtime takes a permanent usage count
on the parent device with it.

In order to remove the need for pm_runtime_irq_safe(), let's gate
the clock directly in the driver. This removes the need to call PM runtime
during idle, and allows us to switch to using CPU_PM later on.

Note that the smartreflex interconnect target module is configured for smart
idle, but the clock does not have autoidle capability, and needs to be gated
manually. If the clock supported autoidle, we would not need to even gate
the clock.

With this change, we can now remove the related quirk flags for ti-sysc
also.

[tony@atomide.com: updated comments on CPU_PM]
Signed-off-by: Tony Lindgren <tony@atomide.com>