For Exynos, flush during hibern8 is sufficient. Manual flush will cause an
increase in power usage.

Link: https://lore.kernel.org/r/ef94af8f273316d50d7f50a0cac9c7be9b9316a1.1598319701.git.kwmad.kim@samsung.comReviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>