size on disk which is f_data.s_size + f_idata.s_size.
f_ohdr.data_start is the base addres of all data and so should
not be changed. *.s_vaddr is the virtual address of the start
size on disk which is f_data.s_size + f_idata.s_size.
f_ohdr.data_start is the base addres of all data and so should
not be changed. *.s_vaddr is the virtual address of the start