fix memory leak around function descriptions

Found by Lsan.

Change-Id: Ia443ed6eb2a20854998a615f3c2bd9fdac156a8c
diff --git a/formula/source/ui/dlg/FormulaHelper.cxx b/formula/source/ui/dlg/FormulaHelper.cxx
index 5805778..6c999bd 100644
--- a/formula/source/ui/dlg/FormulaHelper.cxx
+++ b/formula/source/ui/dlg/FormulaHelper.cxx
@@ -21,6 +21,8 @@
#include <unotools/charclass.hxx>
#include <unotools/syslocale.hxx>

#include <boost/scoped_ptr.hpp>

namespace formula
{

@@ -91,7 +93,7 @@ bool FormulaHelper::GetNextFunc( const OUString&  rFormula,
            const sal_uInt32 nCategoryCount = m_pFunctionManager->getCount();
            for(sal_uInt32 j= 0; j < nCategoryCount && !*ppFDesc; ++j)
            {
                const IFunctionCategory* pCategory = m_pFunctionManager->getCategory(j);
                boost::scoped_ptr<const IFunctionCategory> pCategory(m_pFunctionManager->getCategory(j));
                const sal_uInt32 nCount = pCategory->getCount();
                for(sal_uInt32 i = 0 ; i < nCount; ++i)
                {
diff --git a/include/formula/IFunctionDescription.hxx b/include/formula/IFunctionDescription.hxx
index a3570bb..579d36b 100644
--- a/include/formula/IFunctionDescription.hxx
+++ b/include/formula/IFunctionDescription.hxx
@@ -60,7 +60,7 @@ namespace formula
        ~IFunctionManager() {}
    };

    class SAL_NO_VTABLE IFunctionCategory
    class IFunctionCategory
    {
    public:
        IFunctionCategory(){}
@@ -70,8 +70,7 @@ namespace formula
        virtual sal_uInt32                  getNumber() const = 0;
        virtual OUString             getName() const = 0;

    protected:
        ~IFunctionCategory() {}
        virtual ~IFunctionCategory() {}
    };

    class SAL_NO_VTABLE IFunctionDescription