Add Vsense slot configuration based on the device tree.  Adding this
property enables the slot programming to be moved to the tdm_set_slot
callback.  This in affect sets the slots for the Isense and Vsense and
enabling this these modes are now based on whether these features were
powered on or not.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Link: https://lore.kernel.org/r/20200626154143.20351-3-dmurphy@ti.comSigned-off-by: Mark Brown <broonie@kernel.org>