Preliminarily completed the abstraction of the process in Chapter 5, and
made some changes according to the platform characteristics of
loongarch, but there are still some bugs in the current system that need
to be resolved, and these bugs come from memory management.

Re-modified the address mapping space. This enables the kernel to manage the virtual memory space as if it were directly managing physical memory, and the kernel does not need to perform address translation.

Because the hardware characteristics of loongarch are quite different from those of riscv, the changes in this chapter are relatively large, and because the behavior of privileged instructions is difficult to debug, although the basic work has been completed, it still cannot work normally.

Since the loongArch platform requires software to manage TLB, and its platform difference is quite different from RISC-V, it needs to reorganize the page table and TLB processing

Implement buddy_system_allocator using linked list and tree structure and pass the test

Complete multiprogramming and cooperative scheduling
Fix the bug that the parameter call ABI does not match before

modify batch.rs --> loader.rs

Add loonArch register support, solve ABI call error problem. Complete
batch system.

update readme.md

add uart support