automake: remove unused Automake::FileUtils::up_to_date_p function.

Per thread at:
https://lists.gnu.org/archive/html/automake-patches/2020-04/msg00000.html>
especially:
https://lists.gnu.org/archive/html/automake-patches/2020-05/msg00003.html

* lib/Automake/FileUtils.pm (up_to_date_p): remove.
Nothing in Automake itself uses this.  It is used in Autoconf's
autom4te utility, but Autoconf has its own copy, and the duplication
was impeding auto4mte development, as discussed in the thread above.
(While here, insert missing =over/=back to placate pod2text.)
* NEWS (Miscellanous changes): note this.

1 files changed, 4 insertions, 28 deletions

diff --git a/lib/Automake/FileUtils.pm b/lib/Automake/FileUtils.pm
index 91f5cb217..c004f22e0 100644
--- a/lib/Automake/FileUtils.pm
+++ b/lib/Automake/FileUtils.pm
@@ -52,6 +52,8 @@ use vars qw (@ISA @EXPORT);
 	      &dir_has_case_matching_file &reset_dir_cache
 	      &set_dir_cache_file);
 
+=over 4
+
 =item C<find_file ($file_name, @include)>
 
 Return the first path for a C<$file_name> in the C<include>s.
@@ -179,34 +181,6 @@ sub update_file ($$;$)
 }
 
 
-=item C<up_to_date_p ($file, @dep)>
-
-Is C<$file> more recent than C<@dep>?
-
-=cut
-
-# $BOOLEAN
-# &up_to_date_p ($FILE, @DEP)
-# ---------------------------
-sub up_to_date_p ($@)
-{
-  my ($file, @dep) = @_;
-  my $mtime = mtime ($file);
-
-  foreach my $dep (@dep)
-    {
-      if ($mtime < mtime ($dep))
-	{
-	  verb "up_to_date ($file): outdated: $dep";
-	  return 0;
-	}
-    }
-
-  verb "up_to_date ($file): up to date";
-  return 1;
-}
-
-
 =item C<handle_exec_errors ($command, [$expected_exit_code = 0], [$hint])>
 
 Display an error message for C<$command>, based on the content of
@@ -405,4 +379,6 @@ sub set_dir_cache_file ($$)
     if exists $_directory_cache{$dirname};
 }
 
+=back
+
 1; # for require