regulator: palmas: Add has_regen3 check for TPS659038

Palmas driver is used to cater to even TPS659038 but TPS659038 does not have
REGEN3 resource. Adding another field in the driver data to check on that.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>