regulator: bd71815: fix ramp values

Ramp values are inverted. This caused wrong values written to register
when ramp values were defined in device tree.

Invert values in table to fix this.

Signed-off-by: Kalle Niemi <kaleposti@gmail.com>
Fixes: 1aad3900

 ("regulator: Support ROHM BD71815 regulators")
Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://lore.kernel.org/r/ZmmJXtuVJU6RgQAH@latitude5580
Signed-off-by: Mark Brown <broonie@kernel.org>