regmap: Reorder fields in 'struct regmap_config' to save some memory

On x86_64 and allmodconfig, this shrinks the size of 'struct regmap_config'
from 328 to 312 bytes.

This is usually a win, because this structure is used as a static global
variable.

When moving the kerneldoc fields, I've tried to keep the layout as
consistent as possible, which is not really easy!

Before:
	/* size: 328, cachelines: 6, members: 55 */
	/* sum members: 296, holes: 6, sum holes: 25 */
	/* padding: 7 */
	/* last cacheline: 8 bytes */

After:
	/* size: 312, cachelines: 5, members: 55 */
	/* sum members: 296, holes: 5, sum holes: 16 */
	/* last cacheline: 56 bytes */

For the records, this is also widely used:
	$git grep static.*regmap_config | wc -l
	1327

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/5e039cd8fe415dd7ab3169948c08a5311db9fb9a.1715024007.git.christophe.jaillet@wanadoo.fr


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