cvsserver: Avoid miscounting bytes in Perl v5.8.x

At some point between v5.6 and 5.8 Perl started to assume its input,
output and filehandles are UTF-8. This breaks the counting of bytes
for the CVS protocol, resulting in the client expecting less data
than we actually send, and storing truncated files.
Signed-off-by: NMartin Langhoff <martin@catalyst.net.nz>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

git-cvsserver.perl

@@ -17,6 +17,7 @@
 
 use strict;
 use warnings;
+use bytes;
 
 use Fcntl;
 use File::Temp qw/tempdir tempfile/;