iommu: Fix potential memory leak in iopf_queue_remove_device()

In the Linux kernel, the following vulnerability has been resolved: iommu: Fix potential memory leak in iopf_queue_remove_device() The iopf_queue_remove_device() helper removes a device from the per-iommu iopf queue when PRI is disabled on the device. It responds to all outstanding iopf's with an IOMMU_PAGE_RESP_INVALID code and detaches the device from the queue. However, it fails to release the group structure that represents a group of iopf's awaiting for a response after responding to the hardware. This can cause a memory leak if iopf_queue_remove_device() is called with pending iopf's. Fix it by calling iopf_free_group() after the iopf group is responded.