Remove redundant setup buffer calls.

Nothing should call ssl3_setup_read_buffer or ssl3_setup_write_buffer unless it
intends to write into the buffer. This way buffer management can later be an
implementation detail of the record layer.

Change-Id: Idb0effba00e77c6169764843793f40ec37868b61
Reviewed-on: https://boringssl-review.googlesource.com/4687
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/s3_clnt.c b/ssl/s3_clnt.c
index f42a9ad..d01acae 100644
--- a/ssl/s3_clnt.c
+++ b/ssl/s3_clnt.c
@@ -224,8 +224,7 @@
           buf = NULL;
         }
 
-        if (!ssl3_setup_buffers(s) ||
-            !ssl_init_wbio_buffer(s, 0)) {
+        if (!ssl_init_wbio_buffer(s, 0)) {
           ret = -1;
           goto end;
         }