d_a_npc_zrz mostly done (#2168)

Co-authored-by: hatal175 <hatal175@users.noreply.github.com>

include/rel/d/a/obj/d_a_obj_grave_stone/d_a_obj_grave_stone.h

@@ -40,6 +40,8 @@ public:
     /* 80C1311C */ int Delete();
 
 private:
+    friend class daNpc_zrZ_c;
+
     /* 0x5A0 */ request_of_phase_process_class mPhase;
     /* 0x5A8 */ J3DModel* mpModel;
     /* 0x5AC */ dBgS_ObjAcch mAcch;

include/rel/d/a/obj/d_a_obj_zra_rock/d_a_obj_zra_rock.h

@@ -29,6 +29,8 @@ public:
     void setDemoStart() { mDemoStart = 1; }
 
 private:
+    friend class daNpc_zrZ_c;
+
     /* 0x5A0 */ request_of_phase_process_class mPhaseReq;
     /* 0x5A8 */ J3DModel* mpModelXlu;
     /* 0x5AC */ J3DModel* mpModelOpa;