Kernel: Add support for vmmouse

We add this feature together with the VMWareBackdoor class.
VMWareBackdoor class is responsible for enabling the vmmouse, and then
controlling it from the PS2 mouse IRQ handler.

Kernel/IO.h

@@ -27,6 +27,8 @@
 #pragma once
 
 #include <AK/Types.h>
+#include <Kernel/Arch/i386/CPU.h>
+#include <Kernel/Devices/VMWareBackdoor.h>
 
 namespace IO {
 
@@ -87,6 +89,16 @@ inline void repeated_out16(u16 port, const u8* data, int data_size)
                  : "d"(port));
 }
 
+inline void vmware_out(VMWareCommand& command)
+{
+    command.magic = VMWARE_MAGIC;
+    command.port = VMWARE_PORT;
+    command.si = 0;
+    command.di = 0;
+    asm volatile("in %%dx, %0"
+                 : "+a"(command.ax), "+b"(command.bx), "+c"(command.cx), "+d"(command.dx), "+S"(command.si), "+D"(command.di));
+}
+
 inline void delay()
 {
     // ~3 microsecs