delete /arch/arm/mm/buddy_pmm.c
Remove buddy_pmm.o & buddy_pmm.c. Only remain buddy_pmm.h.
Make kernel success.
Data Size:    619200 Bytes = 604.69 kB = 0.59 MB

	modified:   src/kern-ucore/arch/arm/mm/Makefile
	modified:   src/kern-ucore/arch/arm/mm/pmm.c
Clear tree after make clean.

Avoid the disturbing infomation generated by files in /obj. Focus on the changes in /src, which we really care about.
Add a simple script to help me to make kernel.

This is a ideal start point.
I have removed the pmm_buddy module and run 'make clean' to keep the tree clear, thus the following changes tracked by git will closely
focus on what have changed in the /src directory. Obviously, there is no pint to care about the changes in /obj.
Hollow the mm module.
Try to remove the useless functions in mp.c in /arch/arm/numa. Still leave 3 empty implementations due to outside dependences.
Fighting!:)
Some changes in kern_init(); Not that matters.
EMPTY ARCH
EMPTY ARCH
EMPTY ARCH
prepare for uart
A BRAND NEW START!
The ucore here can only send some characters through the serial port on the board.
Here we go:)
ucore plus with serial port and SysTick interrupt enabled.