selftests/vsock: disable shellcheck SC2317 and SC2119

selftests/vsock: disable shellcheck SC2317 and SC2119

Disable shellcheck rules SC2317 and SC2119. These rules are being
triggered due to false positives. For SC2317, many `return
"${KSFT_PASS}"` lines are reported as unreachable, even though they are
executed during normal runs. For SC2119, the fact that
log_guest/log_host accept either stdin or arguments triggers SC2119,
despite being valid.

Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20251108-vsock-selftests-fixes-and-improvements-v4-12-d5e8d6c87289@meta.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>