Don't modify watch when network queue is full
Don't modify watch when network queue is full

Since 5c460d, we need to watch for WATCH_EVENT_WRITE as long as there are
items queued waiting to be sent, this does not need to be done only when
the network queue is full.

When red_channel_client_set_blocked() is called, as a message is being
sent, WATCH_EVENT_WRITE will already be set, so it does not need to set
it again.
red_channel_client_msg_sent() removes WATCH_EVENT_WRITE, but this will
be done later anyway by red_channel_client_push() if needed.

Since it's redundant, we can remove this.

Signed-off-by: Christophe Fergeau <05b95054a663c388a4e33d95828cb30f0370f8ef@redhat.com>
Acked-by: Frediano Ziglio <55d48b080b2e443e395cde84d2c83b135a4ff48e@redhat.com>

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