Add comphelper/configuration.hxx functions to unusedcode.exclude
Add comphelper/configuration.hxx functions to unusedcode.exclude

The functionality in comphelper/configuration.hxx is used by C++ headers to
simplify configuration access that are generated via
officecfg/Package_cppheader.mk.

Change-Id: I85d26309ec8c4f8ac5cde773fd3298a699bad030

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core