dmaengine: idxd: add driver register helper

dmaengine: idxd: add driver register helper

Add helper functions for dsa-driver registration similar to other
bus-types. In particular, do not require dsa-drivers to open-code the
bus, owner, and mod_name fields. Let registration and unregistration
operate on the 'struct idxd_device_driver' instead of the raw /
embedded 'struct device_driver'.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162637458949.744545.14996726325385482050.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>