use rk_UNCONST

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@15452 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/gssapi/decapsulate.c

@@ -87,7 +87,7 @@ _gssapi_verify_mech_header(u_char **str,
 	       mech->length) != 0)
 	return GSS_S_BAD_MECH;
     p += mech_len;
-    *str = (char *)p;
+    *str = rk_UNCONST(p);
     return GSS_S_COMPLETE;
 }