drm/amdgpu: fix slab-out-of-bounds issue in amdgpu_vm_pt_create

drm/amdgpu: fix slab-out-of-bounds issue in amdgpu_vm_pt_create

Recent code set xcp_id stored from file private data when opening
device to amdgpu bo for accounting memory usage etc, but not all
VMs are attached to this fpriv structure like the vm cases in
amdgpu_mes_self_test, otherwise, KASAN will complain below out
of bound access. And more importantly, VM code should not touch
fpriv structure, so drop fpriv code handling from amdgpu_vm_pt.

[   77.292314] BUG: KASAN: slab-out-of-bounds in amdgpu_vm_pt_create+0x17e/0x4b0 [amdgpu]
[   77.293845] Read of size 4 at addr ffff888102c48a48 by task modprobe/1069
[   77.294146] Call Trace:
[   77.294178]  <TASK>
[   77.294208]  dump_stack_lvl+0x49/0x63
[   77.294260]  print_report+0x16f/0x4a6
[   77.294307]  ? amdgpu_vm_pt_create+0x17e/0x4b0 [amdgpu]
[   77.295979]  ? kasan_complete_mode_report_info+0x3c/0x200
[   77.296057]  ? amdgpu_vm_pt_create+0x17e/0x4b0 [amdgpu]
[   77.297556]  kasan_report+0xb4/0x130
[   77.297609]  ? amdgpu_vm_pt_create+0x17e/0x4b0 [amdgpu]
[   77.299202]  __asan_load4+0x6f/0x90
[   77.299272]  amdgpu_vm_pt_create+0x17e/0x4b0 [amdgpu]
[   77.300796]  ? amdgpu_init+0x6e/0x1000 [amdgpu]
[   77.302222]  ? amdgpu_vm_pt_clear+0x750/0x750 [amdgpu]
[   77.303721]  ? preempt_count_sub+0x18/0xc0
[   77.303786]  amdgpu_vm_init+0x39e/0x870 [amdgpu]
[   77.305186]  ? amdgpu_vm_wait_idle+0x90/0x90 [amdgpu]
[   77.306683]  ? kasan_set_track+0x25/0x30
[   77.306737]  ? kasan_save_alloc_info+0x1b/0x30
[   77.306795]  ? __kasan_kmalloc+0x87/0xa0
[   77.306852]  amdgpu_mes_self_test+0x169/0x620 [amdgpu]

v2: without specifying xcp partition for PD/PT bo, the xcp id is -1.

Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2686
Fixes: 3ebfd221c1a8 ("drm/amdkfd: Store xcp partition id to amdgpu bo")
Signed-off-by: Guchun Chen <guchun.chen@amd.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>