virsh: fflush(stdout) after fputs()

virsh: fflush(stdout) after fputs()

We are not guaranteed that the string we are printing onto stdout
contains '\n' and thus that the stdout is flushed. In fact, I've
met this problem when virsh asked me whether I want to edit the
domain XML again (vshAskReedit()) but the prompt wasn't displayed
(as it does not contain a newline character) and virsh just sat
there waiting for my input, I sat there waiting for virsh's
output. Flush stdout after all fputs()-s  which do not flush
stdout.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>