tls: fix Picotls tx hang issue

Type: fix

Signed-off-by: Simon Zhang <yuwei1.zhang@intel.com>
Change-Id: Id84fbe412c99b39a0754b892ca971dd3e4434264
diff --git a/src/plugins/tlspicotls/tls_picotls.c b/src/plugins/tlspicotls/tls_picotls.c
index d474b7b..a4003c8 100644
--- a/src/plugins/tlspicotls/tls_picotls.c
+++ b/src/plugins/tlspicotls/tls_picotls.c
@@ -459,8 +459,8 @@
   if (!deq_max)
     return deq_max;
 
-  deq_max = clib_min (deq_max, sp->max_burst_size);
-  deq_now = clib_min (deq_max, svm_fifo_max_read_chunk (app_tx_fifo));
+  deq_now = clib_min (deq_max, sp->max_burst_size);
+  deq_now = clib_min (deq_now, svm_fifo_max_read_chunk (app_tx_fifo));
 
   enq_max = svm_fifo_max_enqueue_prod (tls_tx_fifo);
     /** There is no engough enqueue space for one record **/