uacce: Remove mm_exit() op

uacce: Remove mm_exit() op

The mm_exit() op will be removed from the SVA API. When a process dies
and its mm goes away, the IOMMU driver won't notify device drivers
anymore. Drivers should expect to handle a lot more aborted DMA. On the
upside, it does greatly simplify the queue management.

The uacce_mm struct, that tracks all queues bound to an mm, was only
used by the mm_exit() callback. Remove it.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Acked-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Link: https://lore.kernel.org/r/20200423125329.782066-2-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>