dmaengine: idxd: fix memory leak in error handling path of idxd_setup_engines

dmaengine: idxd: fix memory leak in error handling path of idxd_setup_engines

Memory allocated for engines is not freed if an error occurs during
idxd_setup_engines(). To fix it, free the allocated memory in the
reverse order of allocation before exiting the function in case of an
error.

Fixes: 75b911309060 ("dmaengine: idxd: fix engine conf_dev lifetime")
Cc: stable@vger.kernel.org
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Link: https://lore.kernel.org/r/20250404120217.48772-3-xueshuai@linux.alibaba.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>