ASoC: Intel: Skylake: Avoid the use of one-element array

One-element arrays are being deprecated[1]. Replace the one-element
array with a simple value type 'u8 reserved'[2], once it seems this
is just a placeholder for alignment.

[1] https://github.com/KSPP/linux/issues/79
[2] https://github.com/KSPP/linux/issues/86



Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Tested-by: kernel test robot <lkp@intel.com>
Reviewed-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Link: https://github.com/GustavoARSilva/linux-hardening/blob/master/cii/0-day/skylake-20200717.md
Link: https://lore.kernel.org/r/20200717215500.GA13910@embeddedor


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