hwloc: error: point to the FAQ when displaying the big OS error message

(cherry picked from commit open-mpi/hwloc@b191f816f6)
Signed-off-by: Jeff Squyres <jsquyres@cisco.com>

opal/mca/hwloc/hwloc191/hwloc/src/topology.c

@@ -77,7 +77,9 @@ void hwloc_report_os_error(const char *msg, int line)
         fprintf(stderr, "* %s\n", msg);
         fprintf(stderr, "* Error occurred in topology.c line %d\n", line);
         fprintf(stderr, "*\n");
-        fprintf(stderr, "* Please report this error message to the hwloc user's mailing list,\n");
+        fprintf(stderr, "* The following FAQ entry in a recent hwloc documentation may help:\n");
+        fprintf(stderr, "*   What should I do when hwloc reports \"operating system\" warnings?\n");
+        fprintf(stderr, "* Otherwise please report this error message to the hwloc user's mailing list,\n");
 #ifdef HWLOC_LINUX_SYS
         fprintf(stderr, "* along with the output+tarball generated by the hwloc-gather-topology script.\n");
 #else