drm/amdgpu: Implement virt req_ras_err_count

Enable RAS late init  if VF RAS Telemetry is supported.

When enabled, the VF can use this interface to query total
RAS error counts from the host.

The VF FB access may abruptly end due to a fatal error,
therefore the VF must cache and sanitize the input.

The Host allows 15 Telemetry messages every 60 seconds, afterwhich
the host will ignore any more in-coming telemetry messages. The VF will
rate limit its msg calling to once every 5 seconds (12 times in 60 seconds).
While the VF is rate limited, it will continue to report the last
good cached data.

v2: Flip generate report & update statistics order for VF

Signed-off-by: Victor Skvortsov <victor.skvortsov@amd.com>
Acked-by: Tao Zhou <tao.zhou1@amd.com>
Reviewed-by: Zhigang Luo <zhigang.luo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>