Changed to use hypre_Solver_struct approach used in SStruct code for type safety

and to eliminate the need to explicitly cast to/from void *.
Using this approach in ExxonMobil solvers work.

parcsr_mv/_hypre_parcsr_mv.h

@@ -155,7 +155,7 @@ typedef struct
  * hypre_ParVector
  *--------------------------------------------------------------------------*/
 
-typedef struct
+typedef struct hypre_ParVector_struct
 {
    MPI_Comm      comm;
 
@@ -211,7 +211,7 @@ typedef struct
  * Parallel CSR Matrix
  *--------------------------------------------------------------------------*/
 
-typedef struct
+typedef struct hypre_ParCSRMatrix_struct
 {
    MPI_Comm              comm;
    

parcsr_mv/par_csr_matrix.h

@@ -25,7 +25,7 @@
  * Parallel CSR Matrix
  *--------------------------------------------------------------------------*/
 
-typedef struct
+typedef struct hypre_ParCSRMatrix_struct
 {
    MPI_Comm              comm;
 

parcsr_mv/par_vector.h

@@ -28,7 +28,7 @@
  * hypre_ParVector
  *--------------------------------------------------------------------------*/
 
-typedef struct
+typedef struct hypre_ParVector_struct
 {
    MPI_Comm	 comm;