Add support for the Auxiliary Bus, auxiliary_device and auxiliary_driver.
It enables drivers to create an auxiliary_device and bind an
auxiliary_driver to it.

The bus supports probe/remove shutdown and suspend/resume callbacks.
Each auxiliary_device has a unique string based id; driver binds to
an auxiliary_device based on this id through the bus.
Co-developed-by: NKiran Patil <kiran.patil@intel.com>
Co-developed-by: NRanjani Sridharan <ranjani.sridharan@linux.intel.com>
Co-developed-by: NFred Oh <fred.oh@linux.intel.com>
Co-developed-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NKiran Patil <kiran.patil@intel.com>
Signed-off-by: NRanjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: NFred Oh <fred.oh@linux.intel.com>
Signed-off-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NDave Ertman <david.m.ertman@intel.com>
Reviewed-by: NPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: NShiraz Saleem <shiraz.saleem@intel.com>
Reviewed-by: NParav Pandit <parav@mellanox.com>
Reviewed-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NMartin Habets <mhabets@solarflare.com>
Link: https://lore.kernel.org/r/20201113161859.1775473-2-david.m.ertman@intel.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/160695681289.505290.8978295443574440604.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>