mfd: da9052: Add new DA9053 BC chip variant

Add support for a new BC variant of the DA9053 PMIC.

There is one difference between it and the AA, BA and BB.

This patch also corrects a typing mistake in one of the BA
name strings that was incorrectly typed as "ab".

Signed-off-by: Anthony Olech <anthony.olech.opensource@diasemi.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>