ASoC: samsung: smdk_wm8580: remove unused ‘bfs’

In smdk_hw_params(), 'bfs' is initialized and assigned bits based on
params_width, but never used.

We could have removed the whole switch case but then driver might be
relying on checking bits, so I have kept the case for now.

sound/soc/samsung/smdk_wm8580.c: In function ‘smdk_hw_params’:
sound/soc/samsung/smdk_wm8580.c:35:6: warning: variable ‘bfs’ set but not used [-Wunused-but-set-variable]
  int bfs, rfs, ret;

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>