regulator: palmas: fix typo in enable_reg calculation

When setting up .enable_reg for an SMPS regulator, presumably we should
call PALMAS_BASE_TO_REG(PALMAS_SMPS_BASE, ...) rather than using
LDO_BASE. This change makes the LCD panel and HDMI work again on the
NVIDIA Dalmore board anyway.

Fixes: 318dbb02 ("regulator: palmas: Fix SMPS enable/disable/is_enabled")
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Nishanth Menon <nm@ti.com>
Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>