dmaengine: idxd: Move dma_free_coherent() out of spinlocked context

Task may be rescheduled within dma_free_coherent(). So dma_free_coherent()
can't be called between spin_lock() and spin_unlock() to avoid Call Trace:
    Call Trace:
    <TASK>
    dump_stack_lvl+0x37/0x50
    __might_resched+0x16a/0x1c0
    vunmap+0x2c/0x70
    __iommu_dma_free+0x96/0x100
    idxd_device_evl_free+0xd5/0x100 [idxd]
    device_release_driver_internal+0x197/0x200
    unbind_store+0xa1/0xb0
    kernfs_fop_write_iter+0x120/0x1c0
    vfs_write+0x2d3/0x400
    ksys_write+0x63/0xe0
    do_syscall_64+0x44/0xa0
    entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Move it out of the context.

Fixes: 244da66c

 ("dmaengine: idxd: setup event log configuration")
Signed-off-by: Rex Zhang <rex.zhang@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lore.kernel.org/r/20231212022158.358619-2-rex.zhang@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>