dmaengine: idxd: idxd: move remove() bits for idxd 'struct device' to device.c

Move the code related to a ->remove() function for the idxd
'struct device' to device.c to prep for the idxd device
sub-driver in device.c.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162637464768.744545.15797285510999151668.stgit@djiang5-desk3.ch.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>