Remove use of obsolete gccxmlpath

Author: pcanal

Diff for: cmake/modules/RootMacros.cmake

@@ -187,7 +187,7 @@ function(REFLEX_GENERATE_DICTIONARY dictionary)
     OUTPUT ${gensrcdict} ${rootmapname}
     COMMAND ${ROOT_genreflex_CMD}
     ARGS ${headerfiles} -o ${gensrcdict} ${rootmapopts} --select=${selectionfile}
-         --gccxmlpath=${GCCXML_home}/bin ${ARG_OPTIONS}
+         ${ARG_OPTIONS}
          "-I$<JOIN:$<REMOVE_DUPLICATES:$<FILTER:${include_dirs},EXCLUDE,^$>>,;-I>"
          "$<$<BOOL:$<JOIN:${definitions},>>:-D$<JOIN:${definitions},;-D>>"
     DEPENDS ${headerfiles} ${selectionfile} ${ARG_DEPENDS}