alpha:hwrei:rollback for o3

change hwrei back to being a non-control instruction so O3-FS mode will work
add squash in inorder that will catch a hwrei (or any other genric instruction)
that isnt a control inst but changes the PC. Additional testing still needs to be done
for inorder-FS mode but this change will free O3 development back up in the interim

src/arch/alpha/isa/decoder.isa

@@ -935,7 +935,7 @@ decode OPCODE default Unknown::unknown() {
   0x1e: decode PALMODE {
       0: OpcdecFault::hw_rei();
         format BasicOperate {
-          1: hw_rei({{ xc->hwrei(); }}, IsSerializing, IsSerializeBefore, IsControl);
+          1: hw_rei({{ xc->hwrei(); }}, IsSerializing, IsSerializeBefore);
         }
     }