Don't shadow already defined variables

Configure

@@ -912,11 +912,11 @@ my $bn_ops = $fields[$idx_bn_ops];
 my $bn_obj = $fields[$idx_bn_obj];
 my $des_obj = $fields[$idx_des_obj];
 my $bf_obj = $fields[$idx_bf_obj];
-my $md5_obj = $fields[$idx_md5_obj];
-my $sha1_obj = $fields[$idx_sha1_obj];
+$md5_obj = $fields[$idx_md5_obj];
+$sha1_obj = $fields[$idx_sha1_obj];
 my $cast_obj = $fields[$idx_cast_obj];
 my $rc4_obj = $fields[$idx_rc4_obj];
-my $rmd160_obj = $fields[$idx_rmd160_obj];
+$rmd160_obj = $fields[$idx_rmd160_obj];
 my $rc5_obj = $fields[$idx_rc5_obj];
 my $dso_scheme = $fields[$idx_dso_scheme];
 my $shared_target = $fields[$idx_shared_target];