nbd/server: fix TLS negotiation across coroutine context
Merge Request Required Information
Summary of Changes
Backport the same 4 patches as needed in RHEL 9.5 on top of upstream qemu 9.0 to fix regressions with NBD+TLS+iothread.
Approved Development Ticket
All submissions to CentOS Stream must reference an approved ticket in Red Hat Jira. Please follow the CentOS Stream contribution documentation for how to file this ticket and have it approved.
Jira: https://issues.redhat.com/browse/RHEL-40959 scratch build: https://kojihub.stream.rdu2.redhat.com/koji/taskinfo?taskID=4419248