Add a proper vfs driver into the kernel which handles file operations,

fix munmap number, remove the draw calls, make address space an option,
copy only the top 256 bytes of the HHDM and map the ELF code inside
userspace, add safe copying from userspace

kernel/src/arch/x86_64/syscall.rs

@@ -1,7 +1,6 @@
 use core::arch::asm;
 
-use lazy_static::lazy_static;
-use x86_64::instructions::tlb::{self, flush_all};
+use x86_64::instructions::tlb::flush_all;
 
 use crate::arch::x86_64::gdt::{GDT, TSS};