Optimize the code of head_jump.h and stack_check.h.

[Dengerwei]

Background

These code is a little unclear and not easy to read. For the following points:

1. It is better to use the sort API from kernel because it is very stable.
2. The size and address variables of interface functions might be better wrapped into a structure.
3. The size of interface function is stored in two variables, which one is vm/mod_func_size array and the other is mod/orig_##func##_size variable.

Task

Optimize the code of head_jump.h and stack_check.h.

[chenshanpei]

BTW，don't define global variables in header file.