ALSA: ASoC: Blackfin: update SPORT0 port selector (v2)

- Setting the TFS pin selector for SPORT 0 based on whether the selected
  port id F or G. If the port is F then no conflict should exist for the
  TFS. When Port G is selected and EMAC then there is a conflict between
  the PHY interrupt line and TFS.  Current settings prevent the conflict
  by ignoring the TFS pin when Port G is selected. This allows both
  ssm2602 using Port G and EMAC concurrently.

 - some code cleanup

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>