Current regmap has many similar update functions like below,
but the difference is very few.
	regmap_update_bits()
	regmap_update_bits_async()
	regmap_update_bits_check()
	regmap_update_bits_check_async()
Furthermore, we can add *force* write option too in the future.

This patch adds new regmap_update_bits_base() which is feature
merged function. Above functions can be merged into it by macro.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>