dmaengine: idxd: support reporting of halt interrupt

dmaengine: idxd: support reporting of halt interrupt

Unmask the halt error interrupt so it gets reported to the interrupt
handler. When halt state interrupt is received, quiesce the kernel
WQs and unmap the portals to stop submission.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/161894441167.3202472.9485946398140619501.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>