Kernel: Do a big rewrite of PS/2 code

Command sending+response reading is now synchronized. This allows
bochs to properly initialize both mouse and keyboard simultaneously.

Also status register is checked EVERY time read/write to other IO
ports is performed.

kernel/include/kernel/Errors.h

@@ -11,10 +11,6 @@ namespace Kernel
 		ACPI_NoRootSDT,
 		ACPI_NoSuchHeader,
 		ACPI_RootInvalid,
-		PS2_Timeout,
-		PS2_SelfTest,
-		PS2_Reset,
-		PS2_UnsupportedDevice,
 		Ext2_Invalid,
 		Ext2_Corrupted,
 		Ext2_NoInodes,