msm: npu: Fix iommu detaching issue during unloading driver

arm_iommu_detach_device should be called before arm_iommu_release_mapping.

CRs-Fixed: 2270158
Change-Id: I3d778858146ad102a5bb4680306918f328dfcc01
Signed-off-by: Jilai Wang <jilaiw@codeaurora.org>