regmap: provide regmap_field helpers for simple bit operations

We have set/clear/test operations for regmap, but not for regmap_field yet.
So let's introduce regmap_field helpers too.

In many instances regmap_field_update_bits() is used for simple bit setting
and clearing. In these cases the last argument is redundant and we can
hide it with a static inline function.

This adds three new helpers for simple bit operations: set_bits,
clear_bits and test_bits (the last one defined as a regular function).

Signed-off-by: Li Chen <lchen@ambarella.com>
Link: https://lore.kernel.org/r/180eef422c3.deae9cd960729.8518395646822099769@zohomail.com


Signed-off-by: Mark Brown <broonie@kernel.org>