mixin: Convert the component to use the module interface

Replace the comp_drv ops for the mixin component to use the
module_adapter interface. The trigger and get_attribute ops are replaced
with the module_adapter ops which do the exact same thing. The base_cfg
field from struct mixin_data is removed as it is replaced with the
base_cfg in struct module_config and all users have been updated.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>

Author: ranj063