dmaengine: idxd: fix array index when int_handles are being used

dmaengine: idxd: fix array index when int_handles are being used

The index to the irq vector should be local and has no relation to
the assigned interrupt handle. Assign the MSIX interrupt index that is
programmed for the descriptor. The interrupt handle only matters when it
comes to hardware descriptor programming.

Fixes: eb15e7154fbf ("dmaengine: idxd: add interrupt handle request and release support")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162456176939.1121476.3366256009925001897.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>