Fix compilation warnings

--- ADNS.xs

+++ ADNS.xs

@@ -219,7 +219,7 @@ process (adns_state ads)

                 break;

               case adns_r_unknown:

-                sv = newSVpvn (a->rrs.byteblock [i].data, a->rrs.byteblock [i].len);

+                sv = newSVpvn ((const char * const) a->rrs.byteblock [i].data, a->rrs.byteblock [i].len);

                 break;

               default:

@@ -485,6 +485,7 @@ void DESTROY (SV *req)

         cancel = 1

 	CODE:

 {

+        PERL_UNUSED_VAR (ix);

         struct ctx *c;

         if (!(SvROK (req) && SvOBJECT (SvRV (req))