doc: output correct --help references with --program-prefix

* src/system.h (emit_ancillary_info): Take the invariant PROGRAM_NAME
as a parameter, so that consistent references are made to online docs
and texinfo nodes, when a --program-prefix is in place.  Note the
man pages don't need this fix as they're generated before the program
prefix is used.
* NEWS: Mention the improvements in references to online documentation.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/cat.c b/src/cat.c
index 267864f20..c7bb7e132 100644
--- a/src/cat.c
+++ b/src/cat.c
@@ -118,7 +118,7 @@ Examples:\n\
   %s        Copy standard input to standard output.\n\
 "),
               program_name, program_name);
-      emit_ancillary_info ();
+      emit_ancillary_info (PROGRAM_NAME);
     }
   exit (status);
 }