vgsp-sema: re-arm ring/push-buffer discovery latches on channel registration; scanner streams anonymous high-VA buffers

Second-client wedge fix: a new GSP session re-registers the same channel
handles/ranks, but the per-rank one-shot ring/push-buffer discovery latches
stayed set from the previous session, so the new session's ring was never
re-autopinned (ring_auto=0 pb=0/0, nomap growing) and the guest spun in its
channel-creation wait. svc_chan_rearm_rank() clears the latches on every
channel registration; all post-fix cycles launch the second client.

Scanner: guest_pin_stream.py now streams the client's anonymous high-VA
mappings (cudaMalloc buffers were skipped by the old len(parts)<6 check),
so the host can learn their pages.

Diagnostics: PT-window lines, per-window first words, post-OK qmdwin
w48..59. Remaining: the fill-time svc_ipin_lookup miss for the second
client's a/b/c pins (they exist in the pin log but are not seen at fill
time) - next session.

0 files changed, 0 insertions, 0 deletions