Fix racy test.

With exchanges == renego period, sometimes the connection will be closed by
the client before the server had time to read the ClientHello, making the test
fail. The extra exchange avoids that.
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 51c3fd0..8bf7d97 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -1088,9 +1088,10 @@
             -S "SSL - An unexpected message was received from our peer" \
             -S "failed"
 
+# one extra exchange to be able to complete renego
 run_test    "Renegotiation: periodic, just above period" \
             "$P_SRV debug_level=3 exchanges=9 renegotiation=1 renego_period=3" \
-            "$P_CLI debug_level=3 exchanges=3 renegotiation=1" \
+            "$P_CLI debug_level=3 exchanges=4 renegotiation=1" \
             0 \
             -c "client hello, adding renegotiation extension" \
             -s "received TLS_EMPTY_RENEGOTIATION_INFO" \
@@ -1106,7 +1107,7 @@
 
 run_test    "Renegotiation: periodic, two times period" \
             "$P_SRV debug_level=3 exchanges=9 renegotiation=1 renego_period=3" \
-            "$P_CLI debug_level=3 exchanges=6 renegotiation=1" \
+            "$P_CLI debug_level=3 exchanges=7 renegotiation=1" \
             0 \
             -c "client hello, adding renegotiation extension" \
             -s "received TLS_EMPTY_RENEGOTIATION_INFO" \