libqemuutil has two definitions of qemu_set_fd_handler.  This
is not needed since the only users of the function are
qemu-io.c and the emulators, both of which already include
util/main-loop.c.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <d0c5aa88-029e-4328-7a53-482a3010c5f8@redhat.com>
Tested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210318155519.1224118-2-armbru@redhat.com>