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.

### Reference issue
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See merge request libeigen/eigen!2036

Eigen/Eigenvalues

@@ -15,6 +15,7 @@
 #include "Householder"
 #include "LU"
 #include "Geometry"
+#include "Sparse"  // Needed by ComplexQZ.
 
 #include "src/Core/util/DisableStupidWarnings.h"
 

Eigen/src/Eigenvalues/ComplexQZ.h

@@ -14,8 +14,6 @@
 #ifndef EIGEN_COMPLEX_QZ_H_
 #define EIGEN_COMPLEX_QZ_H_
 
-#include "../../Sparse"
-
 // IWYU pragma: private
 #include "./InternalHeaderCheck.h"
 
@@ -126,9 +124,7 @@ class ComplexQZ {
             computeQZ ? n : (MatrixType::ColsAtCompileTime == Eigen::Dynamic ? 0 : MatrixType::ColsAtCompileTime)),
         m_ws(2 * n),
         m_computeQZ(computeQZ),
-        m_maxIters(maxIters){
-
-        };
+        m_maxIters(maxIters) {}
 
   /** \brief Constructor. computes the QZ decomposition of given matrices
    * upon creation
@@ -178,14 +174,14 @@ class ComplexQZ {
    *
    * \returns \c Success if computation was successfull, \c NoConvergence otherwise.
    */
-  ComputationInfo info() const { return m_info; };
+  ComputationInfo info() const { return m_info; }
 
   /** \brief number of performed QZ steps
    */
   unsigned int iterations() const {
     eigen_assert(m_isInitialized && "ComplexQZ is not initialized.");
     return m_global_iter;
-  };
+  }
 
  private:
   Index m_n;

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.