Refactor COM port support, to get rid of global variables in library

xtoskrnl/includes/hli.h

@@ -56,7 +56,6 @@ HlGetRunLevel(VOID);
 XTCDECL
 XTSTATUS
 HlInitializeComPort(IN OUT PCPPORT Port,
-                    IN ULONG PortNumber,
                     IN PUCHAR PortAddress,
                     IN ULONG BaudRate);