More ComplexQZ fixes.

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### Description
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More ComplexQZ fixes.

Extra semicolons are triggering some warnings and errors with `-Werror`.
Moved the `Sparse` import up to the umbrella header to avoid IWYU exports.

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See merge request libeigen/eigen!2036

Eigen/src/SparseCholesky/SimplicialCholesky_impl.h

@@ -89,7 +89,7 @@ struct simpl_chol_helper {
         m_set[u] = v;
         u = next;
       }
-    };
+    }
   };
 
   // Computes the higher adjacency pattern by transposing the input lower adjacency matrix.