boost::unordered_set is not used anymore

Change-Id: I0d38b254a1a23c124247a7b747f5d1331c571f54
Reviewed-on: https://gerrit.libreoffice.org/21977Reviewed-by: Noel Grandin <noelgrandin@gmail.com>
Tested-by: Noel Grandin <noelgrandin@gmail.com>

reportdesign/inc/pch/precompiled_rptui.hxx

@@ -62,7 +62,6 @@
 #include <boost/mem_fn.hpp>
 #include <boost/noncopyable.hpp>
 #include <boost/shared_array.hpp>
-#include <boost/unordered_set.hpp>
 #include <osl/conditn.h>
 #include <osl/conditn.hxx>
 #include <osl/diagnose.h>

sd/inc/pch/precompiled_sdui.hxx

@@ -58,7 +58,6 @@
 #include <boost/noncopyable.hpp>
 #include <boost/optional.hpp>
 #include <boost/shared_array.hpp>
-#include <boost/unordered_set.hpp>
 #include <osl/diagnose.h>
 #include <osl/diagnose.hxx>
 #include <osl/doublecheckedlocking.h>

sw/inc/pch/precompiled_msword.hxx

@@ -67,7 +67,6 @@
 #include <boost/noncopyable.hpp>
 #include <boost/optional.hpp>
 #include <boost/shared_array.hpp>
-#include <boost/unordered_set.hpp>
 #include <osl/diagnose.h>
 #include <osl/diagnose.hxx>
 #include <osl/doublecheckedlocking.h>