In order to enable and build with SPL_REGULATOR_PWM we need to have both
SPL_DM_REGULATOR and SPL_DM_PWM enabled. Build-wise, we can have SPL
have PWM regulator support without enabling it in U-Boot itself so drop
that dependency.
Signed-off-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>