ASoC: mchp-spdiftx: remove references to mchp_i2s_caps

commit 403fcb51

 upstream.

Remove references to struct mchp_i2s_caps as they are not used.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220727090814.2446111-3-claudiu.beznea@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>