drm/amdkfd: Fix kernel warning during topology setup

commit cf97eb7e upstream.

This patch fixes the following kernel warning seen during
driver load by correctly initializing the p2plink attr before
creating the sysfs file:

[  +0.002865] ------------[ cut here ]------------
[  +0.002327] kobject: '(null)' (0000000056260cfb): is not initialized, yet kobject_put() is being called.
[  +0.004780] WARNING: CPU: 32 PID: 1006 at lib/kobject.c:718 kobject_put+0xaa/0x1c0
[  +0.001361] Call Trace:
[  +0.001234]  <TASK>
[  +0.001067]  kfd_remove_sysfs_node_entry+0x24a/0x2d0 [amdgpu]
[  +0.003147]  kfd_topology_update_sysfs+0x3d/0x750 [amdgpu]
[  +0.002890]  kfd_topology_add_device+0xbd7/0xc70 [amdgpu]
[  +0.002844]  ? lock_release+0x13c/0x2e0
[  +0.001936]  ? smu_cmn_send_smc_msg_with_param+0x1e8/0x2d0 [amdgpu]
[  +0.003313]  ? amdgpu_dpm_get_mclk+0x54/0x60 [amdgpu]
[  +0.002703]  kgd2kfd_device_init.cold+0x39f/0x4ed [amdgpu]
[  +0.002930]  amdgpu_amdkfd_device_init+0x13d/0x1f0 [amdgpu]
[  +0.002944]  amdgpu_device_init.cold+0x1464/0x17b4 [amdgpu]
[  +0.002970]  ? pci_bus_read_config_word+0x43/0x80
[  +0.002380]  amdgpu_driver_load_kms+0x15/0x100 [amdgpu]
[  +0.002744]  amdgpu_pci_probe+0x147/0x370 [amdgpu]
[  +0.002522]  local_pci_probe+0x40/0x80
[  +0.001896]  work_for_cpu_fn+0x10/0x20
[  +0.001892]  process_one_work+0x26e/0x5a0
[  +0.002029]  worker_thread+0x1fd/0x3e0
[  +0.001890]  ? process_one_work+0x5a0/0x5a0
[  +0.002115]  kthread+0xea/0x110
[  +0.001618]  ? kthread_complete_and_exit+0x20/0x20
[  +0.002422]  ret_from_fork+0x1f/0x30
[  +0.001808]  </TASK>
[  +0.001103] irq event stamp: 59837
[  +0.001718] hardirqs last  enabled at (59849): [<ffffffffb30fab12>] __up_console_sem+0x52/0x60
[  +0.004414] hardirqs last disabled at (59860): [<ffffffffb30faaf7>] __up_console_sem+0x37/0x60
[  +0.004414] softirqs last  enabled at (59654): [<ffffffffb307d9c7>] irq_exit_rcu+0xd7/0x130
[  +0.004205] softirqs last disabled at (59649): [<ffffffffb307d9c7>] irq_exit_rcu+0xd7/0x130
[  +0.004203] ---[ end trace 0000000000000000 ]---

Fixes: 0f28cca8 ("drm/amdkfd: Extend KFD device topology to surface peer-to-peer links")
Signed-off-by: Mukul Joshi <mukul.joshi@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>