regulator: Add property for I2C level shifter

By setting nxp,i2c-lt-enable the I2C level translator is
enabled.

Signed-off-by: Per-Daniel Olsson <perdo@axis.com>
Signed-off-by: Rickard x Andersson <rickaran@axis.com>
Link: https://lore.kernel.org/r/20220429072211.24957-1-rickaran@axis.com
Signed-off-by: Mark Brown <broonie@kernel.org>