BUG/MEDIUM: spoe: Allow producer to read and to forward shutdown on request side

This is mandatory to correctly set right timeout on the stream. Else the client
timeout is never set. So only SPOE processing timeout will be evaluated. If it
is not defined (ie infinity), the stream can be blocked for a while, waiting the
SPOA reply. Of course, this is not a good idea to let the SPOE processing
timeout undefined, but it can happen.

This patch must be backported in 1.8.
diff --git a/src/flt_spoe.c b/src/flt_spoe.c
index 5b6e253..15317d1 100644
--- a/src/flt_spoe.c
+++ b/src/flt_spoe.c
@@ -3088,7 +3088,7 @@
 	}
 
   out:
-	if (!ret) {
+	if (!ret && (chn->flags & CF_ISRESP)) {
                 channel_dont_read(chn);
                 channel_dont_close(chn);
 	}