Rewrite init app in C, introduce MSL (MOP3 System Library)

kernel/amd64/syscallentry.S

@@ -5,7 +5,6 @@
 .global amd64_syscall_entry
 amd64_syscall_entry:
   cli
-  swapgs
 
   movq %rsp, %gs:0
   movq %gs:8, %rsp
@@ -20,15 +19,10 @@ amd64_syscall_entry:
 
   push_regs
 
-  swapgs
-
   cld
 
   movq %rsp, %rdi
 
-  movq %cr3, %rax
-  pushq %rax
-
   movq %rsp, %rbp
 
   subq $8, %rsp
@@ -38,20 +32,9 @@ amd64_syscall_entry:
 
   movq %rbp, %rsp
 
-  popq %rax
-  movq %rax, %cr3
-
   pop_regs
   
-  swapgs
-
-  addq $16, %rsp
-  popq %rcx
-  addq $8, %rsp
-  popq %r11
-  addq $16, %rsp
+  addq $56, %rsp
   movq %gs:0, %rsp
   
-  swapgs
-
   sysretq