[klibc(checklist)] klibc initial implementation checklist

Header files:
- [x] stdarg.h
- [x] stdbool.h
- [x] stddef.h
- [x] stdint.h
- [x] string.h
- [x] stdlib.h

Symbols:
- [x] string.h:
- [x] memcmp
- [x] memset
- [x] memcpy
- [x] memmove
- [x] strlen
- [x] strcmp

- [x] stdarg.h:
- [x] va_start
- [x] va_arg
- [x] va_end
- [x] va_copy

- [ ] stdlib.h:
- [ ] malloc
- [ ] free

Types:
- [x] uint8_t
- [x] uint16_t
- [x] uint32_t
- [x] bool:
- [x] true
- [x] false
- [x] va_list