Add a news item about MPI::IN_PLACE. Refs trac:1465.

This commit was SVN r19421.

The following Trac tickets were found above:
  Ticket 1465 --> https://svn.open-mpi.org/trac/ompi/ticket/1465

NEWS

@@ -38,6 +38,7 @@ Trunk (not on release branches yet)
 1.3 (not released yet)
 ---
 
+- Fix the type of the C++ constant MPI::IN_PLACE.
 - Various enhancements to the openib BTL:
   - Added btl_openib_if_[in|ex]clude MCA parameters for
     including/excluding comma-delimited lists of HCAs and ports.