scsi: ufs: Make sure clk scaling happens only when HBA is runtime ACTIVE

If someone plays with the UFS clk scaling devfreq governor through sysfs,
ufshcd_devfreq_scale may be called even when HBA is not runtime ACTIVE.
This can lead to unexpected error. We cannot just protect it by calling
pm_runtime_get_sync() because that may cause a race condition since HBA
runtime suspend ops need to suspend clk scaling. To fix this call
pm_runtime_get_noresume() and check HBA's runtime status. Only proceed if
HBA is runtime ACTIVE, otherwise just bail.

governor_store
 devfreq_performance_handler
  update_devfreq
   devfreq_set_target
    ufshcd_devfreq_target
     ufshcd_devfreq_scale

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Stanley Chu <[email protected]>
Signed-off-by: Can Guo <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

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