Fix MPI_Attr_put on big-endian systems

Cast the pointer to the correct type so that
it works on big-endian systems
Signed-off-by: Michael Blocksome <blocksom@us.ibm.com>
Signed-off-by: Junchao Zhang <jczhang@mcs.anl.gov>

src/binding/f77/buildiface

@@ -2386,7 +2386,7 @@ sub addrint_in_decl {
 }
 sub addrint_in_arg {
     my $count = $_[0];
-    print $OUTFD "(void *)(*(MPIR_Pint *)v$count)";
+    print $OUTFD "(void *)((MPIR_Pint)*(MPI_Fint *)v$count)";
 }
 
 sub attrint_ctof {