ASoC: rt1308: clarify expression

cppcheck warning:

sound/soc/codecs/rt1308.c:676:40: style: Boolean result is used in
bitwise operation. Clarify expression with
parentheses. [clarifyCondition]
  pll_code.k_code << RT1308_PLL1_K_SFT |
                                       ^

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210302212527.55158-8-pierre-louis.bossart@linux.intel.com


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