Thrift: Forgot to dereference a pointer.

Summary:
This didn't get updated when the interface changed,
and the cast silenced the warning message.  Stupid C.

Reviewed By: mcslee

Test Plan: Trust Chad Walters.

Revert Plan: ok


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665457 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/cpp/src/transport/TZlibTransport.cpp b/lib/cpp/src/transport/TZlibTransport.cpp
index ea0b0a4..27aa350 100644
--- a/lib/cpp/src/transport/TZlibTransport.cpp
+++ b/lib/cpp/src/transport/TZlibTransport.cpp
@@ -238,7 +238,7 @@
   // Don't try to be clever with shifting buffers.
   // If we have enough data, give a pointer to it,
   // otherwise let the protcol use its slow path.
-  if (readAvail() >= (int)len) {
+  if (readAvail() >= (int)*len) {
     *len = (uint32_t)readAvail();
     return urbuf_ + urpos_;
   }