systemc: Get rid of a duplicated base class initializer for sc_fifo.

These were consistent, but redundant and incorrect none the less.

Change-Id: I9ff7fdb9c83f9a8af6fbe969c6c73b9aab8967ad
Reviewed-on: https://gem5-review.googlesource.com/c/14136
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

src/systemc/ext/channel/sc_fifo.hh

@@ -196,8 +196,7 @@ class sc_fifo : public sc_fifo_in_if<T>,
 
   private:
     // Disabled
-    sc_fifo(const sc_fifo<T> &) :
-            sc_fifo_in_if<T>(), sc_fifo_in_if<T>(), sc_prim_channel()
+    sc_fifo(const sc_fifo<T> &) : sc_fifo_in_if<T>(), sc_prim_channel()
     {}
     sc_fifo &operator = (const sc_fifo<T> &) { return *this; }