misc: cs35l41: Remove unused pdn variable

Remove pdn variable that was made redundant in an earlier patch.

Fixes: c2f14cc2 ("ASoC: cs35l41: Fix use of an uninitialised variable")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20210916082346.12001-1-ckeepax@opensource.cirrus.com


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