Update Kokkos library in LAMMPS to v2.7.24

lib/kokkos/example/virtual_functions/classes.cpp

@@ -0,0 +1,26 @@
+#include<classes.hpp>
+
+KOKKOS_FUNCTION
+Foo::Foo() {
+  val = 0;
+} 
+
+KOKKOS_FUNCTION
+Foo_1::Foo_1() {
+  val = 1;
+}
+
+KOKKOS_FUNCTION
+int Foo_1::value() {
+  return val;  
+}
+
+KOKKOS_FUNCTION
+Foo_2::Foo_2() {
+  val = 2;
+}
+
+KOKKOS_FUNCTION
+int Foo_2::value() {
+  return val;  
+}