Fix undef warnings in usedl detection

Author: bingos

t/03-xsstatic.t

@@ -13,7 +13,7 @@ use Test::More;
 
 plan skip_all => "Disabled as broken perl installs give false negative"
   # if not static perl, and not author
-  if $Config{usedl} eq 'define' and !$ENV{AUTHOR_TESTING};
+  unless !$Config{usedl} and $ENV{AUTHOR_TESTING};
 plan skip_all => "ExtUtils::CBuilder not installed or couldn't find a compiler"
   unless have_compiler();
 plan skip_all => 'Shared perl library' if $Config{useshrplib} eq 'true';

t/lib/MakeMaker/Test/Setup/XS.pm

@@ -244,7 +244,7 @@ sub setup_xs {
 
 sub list_static {
   (
-    ($Config{usedl} ne 'define' ? [ 'basic', '', '' ] : ()), # still needs testing on static perl
+    ( !$Config{usedl} ? [ 'basic', '', '' ] : ()), # still needs testing on static perl
     [ 'static', '', '' ],
     [ 'basic', ' static', '_static' ],
     [ 'multi', ' static', '_static' ],