ASoC: Intel: Skylake: use module_pin info for unbind

in_pin and out_pin list for a module has the information about
the module that are bound together. So we can directly look at
pin information of module for binding and unbind.

As a result the preinitialized dapm_path_last we had is removed
and code and memory optimzed.

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

sound/soc/intel/skylake/skl-topology.h

@@ -280,11 +280,6 @@ struct skl_pipeline {
 	struct list_head node;
 };
 
-struct skl_dapm_path_list {
-	struct snd_soc_dapm_path *dapm_path;
-	struct list_head node;
-};
-
 static inline struct skl *get_skl_ctx(struct device *dev)
 {
 	struct hdac_ext_bus *ebus = dev_get_drvdata(dev);