base: Add type alias for raw pointer in RefCountingPtr

Change-Id: Ied2204566a8fc5c34fb4702301051b8e5ab84ffe
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13717
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

src/base/refcnt.hh

@@ -119,6 +119,9 @@ class RefCounted
 template <class T>
 class RefCountingPtr
 {
+  public:
+    using PtrType = T*;
+
   protected:
     /** Convenience aliases for const/non-const versions of T w/ friendship. */
     /** @{ */