Consolidate common SONiC Python-language functionality into one shared package (sonic-py-common) and eliminate duplicate code.
The package currently includes three modules:
- daemon_base
- device_info
- logger
slave.mk: add SONIC_PLATFORM_API_PY2 as dependency of host
sonic_debian_extension.j2: install sonic_daemon_base and Mellanox-specific sonic_platform on host
mlnx-platform-api.mk: export mlnx_platform_api_py2_wheel_path for sonic_debian_extension.j2
sonic-daemon-base.mk: export daemon_base_py2_wheel_path for sonic_debian_extension.j2
daemon_base.py: hind unnecessary dependency of swss_common on host
