CPAN.pm: Fix "Redundant argument in sprintf"

RT #122159

5.22-tobe includes a new warning type, "Redundant argument in sprintf".
Stop CPAN emitting such a warning.

To quote Andreas from the ticket:
"I'll jump to 2.12 then in my copy and will not release a 2.11"

cpan/CPAN/lib/CPAN.pm

@@ -2,7 +2,7 @@
 # vim: ts=4 sts=4 sw=4:
 use strict;
 package CPAN;
-$CPAN::VERSION = '2.10';
+$CPAN::VERSION = '2.11';
 $CPAN::VERSION =~ s/_//;
 
 # we need to run chdir all over and we would get at wrong libraries
@@ -318,7 +318,6 @@ Enter 'h' for help.
 
 },
                                  $CPAN::VERSION,
-                                 $rl_avail
                                 )
     }
     my($continuation) = "";