Remove numeric overloading of Getopt::Long callback functions. (Closes: #479434)

The numeric overloading introduced in Getopt::Long 2.36 broke
lintian and libvcp-perl.

Dual-lived module, fixed on the CPAN side in 2.37_01.

[rt.cpan.org #35759]
diff --git a/lib/Getopt/Long.pm b/lib/Getopt/Long.pm
index f44e615..b5f94b1 100644
--- a/lib/Getopt/Long.pm
+++ b/lib/Getopt/Long.pm
@@ -1483,7 +1483,6 @@ sub name {
 use overload
   # Treat this object as an oridinary string for legacy API.
   '""'	   => \&name,
-  '0+'	   => sub { 0 },
   fallback => 1;
 
 1;