SMB sharing on FIPS enabled hosts with Samba broken
Description of problem:
Similar to #2593 , newer security features on GNU+Linux host OSes are continuing
to break communication with guests running older OSes.

QEMU executes the `smbd` process in [slirp.c](net/slirp.c) to facilitate the SMB
sharing between guest and host.

The host `smbd` process links in GnuTLS for authentication ciphers and algorithm
primitives.  When `smbd` processes SMB requests from these older OS's SMB implementations,
it errors out with error lines:

`Failed to setup SPNEGO negTokenInit request`

`Failed to start SPNEGO handler for negprot OID list!`
Steps to reproduce:
1. Access a GNU+Linux machine with GnuTLS library in FIPS mode which `smbd` links against
2. Run `qemu-system-*` with an older guest OS with a `smb` share to host
3. See errors in `/tmp/qemu.smb*/log.smbd`
Additional information:
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