do not show cache numbers when they are -1
do not show cache numbers when they are -1

This commit was SVN r318.

ggouaillardet/hwloc,shekkbuilder/hwloc,ggouaillardet/hwloc,ggouaillardet/hwloc,shekkbuilder/hwloc,shekkbuilder/hwloc,ggouaillardet/hwloc,shekkbuilder/hwloc