ASoC: dpcm: Don't apply symmetry for BE with hw param fixup

If be_hw_param_fixup is defined for BE then it will
force the BE to a specific configuration supported
by HW. In this case don't apply symmetry.

Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>