ASoC: mediatek: mt8192-mt6359: simplify ops for Capture1 DAI link

1. Uses rtd->dev to get the device.
2. Generalizes the variable name.

Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Link: https://lore.kernel.org/r/20210203032201.2882158-4-tzungbi@google.com


Signed-off-by: Mark Brown <broonie@kernel.org>