ASoC: simple-card-utils: add asoc_simple_card_of_parse_tdm()

Current simple card drivers are using asoc_simple_dai's tx_slot_mask,
rx_slot_mask, slots, slot_width directly to parse TDM.
Encapsulation is one of simple card util's purpose.
Let's add asoc_simple_card_of_parse_tdm for it.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>