When adding virDomainGetVcpusFlags in commit ea3f5c68, I did
enough rebasing that the doc comments in libvirt.c no longer
matched the final chosen enum names in libvirt.h.

And now we've gone ahead and deprecated the names
VIR_DOMAIN_VCPU_{LIVE,CONFIG}.

* src/libvirt.c (virDomainGetVcpusFlags): Fix comment.