drm/amdgpu: update fence ptr with context:seqno

log context:seqno of the fence during timeout rather
than logging fence pointer.

Reviewed-by: Arvind Yadav <Arvind.Yadav@amd.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>