Clean up PS/2 keyboard driver, new IPC mechanism MBus (message bus)

kernel/kmain.c

@@ -17,6 +17,7 @@
 #include "vmm/vmm.h"
 #include "cpu/hang.h"
 #include "cpu/gdt.h"
+#include "ipc/mbus/mbus.h"
 
 void log_bootinfo(void) {
   char buf[100];
@@ -48,6 +49,7 @@ void kmain(void) {
   pmm_init();
   vmm_init();
   randcrypto_init();
+  ipc_mbusinit();
   dev_init();
   storedev_init();
   diskpart_init();