mem: Deleting this init() method was accidentally dropped during rebase.

Deleting this init() method was part of a change just committed, but
was accidentally dropped during a rebase.

Change-Id: I0f22778596ed11e182f3111d9999a0fef727f6cc
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17688
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

src/mem/xbar.hh

@@ -408,8 +408,6 @@ class BaseXBar : public MemObject
 
     virtual ~BaseXBar();
 
-    void init() override;
-
     /** A function used to return the port associated with this object. */
     Port &getPort(const std::string &if_name,
                   PortID idx=InvalidPortID) override;