Test store map value in map

[Alan-Jowett]

This pull request primarily involves changes to the CMakeLists.txt file and the addition of a new source file src/store_map_value_in_map.c. The changes in CMakeLists.txt include the addition of a new custom command and target for the new source file. The new source file src/store_map_value_in_map.c defines two BPF array maps and a function to lookup a value from one map and store it in the other.

• CMakeLists.txt: Added a new custom command that compiles the new source file src/store_map_value_in_map.c to generate an object file store_map_value_in_map.o [1]. Also, added this new object file to the custom target samples ALL [2].

• src/store_map_value_in_map.c: This is a new file that includes the definition of two BPF array maps named map1 and map2 and a function func. This function looks up a value from map1 and stores it in map2.