ASoC: sst-bxt-rt298: fix obsoleted initializers for array

Sparse reports below warnings.

bxt_rt298.c:275:9: warning: obsolete array initializer, use C99 syntax
bxt_rt298.c:290:9: warning: obsolete array initializer, use C99 syntax
bxt_rt298.c:304:9: warning: obsolete array initializer, use C99 syntax
bxt_rt298.c:317:9: warning: obsolete array initializer, use C99 syntax
bxt_rt298.c:331:9: warning: obsolete array initializer, use C99 syntax
bxt_rt298.c:344:9: warning: obsolete array initializer, use C99 syntax
bxt_rt298.c:357:9: warning: obsolete array initializer, use C99 syntax

There's no need to use obsoleted way. This commit fixes it.

Fixes: 76016322 (ASoC: Intel: Add Broxton-P machine driver)
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>