vgsp-sema: scope CE/GR rank assignment to the owning client (ISSUE-0002)

r78 validation of the client-scoped deletion: the boot session's CeUtils
scrubber channel (client != the UVM client, entries=4096) stayed
registered as intended, but it consumed CE rank 0 and every UVM channel's
rank shifted by one. Ring autopin and push-buffer pairing derive the ring
and pool-semaphore offsets from the rank (0x121010000 + 0x30000*rank,
0x121000000 + 4*rank), so the first client's pairing went to the wrong
offsets and the guest wedged on an rwsem (sysrq: rwsem_spin_on_owner).

Rank is now counted only among live channels of the same owning client;
the UVM client's channels keep ranks 0..5 and the kernel/GPU-global
scrubber gets its own (unused for the pool layout) rank. Missing clients
keep the old counting.

0 files changed, 0 insertions, 0 deletions