arch-arm: Add invalidate method to the TlbEntry

This is needed for compliance with the AssociativeCache
container. It will call the invalidate method when
invalidating the TLB entry

Change-Id: Idb1bc40b5aea8c475146700c81ab79d9980f745d
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

src/arch/arm/pagetable.hh

@@ -351,6 +351,13 @@ struct TlbEntry : public ReplaceableEntry, Serializable
         std::swap(xs, rhs.xs);
     }
 
+    /** Need for compliance with the AssociativeCache interface */
+    void
+    invalidate()
+    {
+        valid = false;
+    }
+
     void
     updateVaddr(Addr new_vaddr)
     {