drm/amdkfd: Destroy KFD debugfs after destroy KFD wq

In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Destroy KFD debugfs after destroy KFD wq Since KFD proc content was moved to kernel debugfs, we can't destroy KFD debugfs before kfd_process_destroy_wq. Move kfd_process_destroy_wq prior to kfd_debugfs_fini to fix a kernel NULL pointer problem. It happens when /sys/kernel/debug/kfd was already destroyed in kfd_debugfs_fini but kfd_process_destroy_wq calls kfd_debugfs_remove_process. This line debugfs_remove_recursive(entry->proc_dentry); tries to remove /sys/kernel/debug/kfd/proc/<pid> while /sys/kernel/debug/kfd is already gone. It hangs the kernel by kernel NULL pointer. (cherry picked from commit 0333052d90683d88531558dcfdbf2525cc37c233)