dmaengine: dmatest: Fix dmatest waiting less when interrupted

dmaengine: dmatest: Fix dmatest waiting less when interrupted

Change the "wait for operation finish" logic to take interrupts into
account.

When using dmatest with idxd DMA engine, it's possible that during
longer tests, the interrupt notifying the finish of an operation
happens during wait_event_freezable_timeout(), which causes dmatest to
cleanup all the resources, some of which might still be in use.

This fix ensures that the wait logic correctly handles interrupts,
preventing premature cleanup of resources.

Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202502171134.8c403348-lkp@intel.com
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20250305230007.590178-1-vinicius.gomes@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>