Just fall through to default when the upper bits are not as expected to

avoid lockup, though it may lockup anyway.  We should respond with a bus
error or something instead.

src_Core/Core/CoreW.bsv

@@ -363,8 +363,8 @@ module mkCoreW #(Reset dm_power_on_reset)
         res[plic_slave_num] = True;
       else
         res[default_slave_num] = True;
-      Bit #(24) topBits = truncateLSB(addr); //XXX TODO Tag controller masks to 40 bits
-      if (topBits != 0) res = replicate(False);
+      //Bit #(24) topBits = truncateLSB(addr); //XXX TODO Tag controller masks to 40 bits
+      //if (topBits != 0) res = replicate(False);
       return res;
    endfunction