Update tilcdc driver to set the state of the pins to:
- "default on resume
- "sleep" on suspend

By optionally putting the pins into sleep state in the suspend callback
we can accomplish two things.
- minimize current leakage from pins and thus save power,
- prevent the IP from driving pins output in an uncontrolled manner,
which may happen if the power domain drops the domain regulator.
Signed-off-by: NDave Gerlach <d-gerlach@ti.com>
Signed-off-by: NDarren Etheridge <detheridge@ti.com>
Signed-off-by: NJyri Sarha <jsarha@ti.com>
Reviewed-by: NTomi Valkeinen <tomi.valkeinen@ti.com>