[hbirr] 18206: Disable the serial debug output if the com port doesn't exist.

Disable the serial debug output if the com port doesn't exist.
Modified: trunk/reactos/ntoskrnl/kd/kdio.c
  _____  

Modified: trunk/reactos/ntoskrnl/kd/kdio.c
--- trunk/reactos/ntoskrnl/kd/kdio.c	2005-10-02 08:40:49 UTC (rev
18205)
+++ trunk/reactos/ntoskrnl/kd/kdio.c	2005-10-02 09:42:12 UTC (rev
18206)
@@ -171,7 +171,11 @@

         DispatchTable->KdpPrintRoutine = KdpSerialDebugPrint;
 
         /* Initialize the Port */
-        KdPortInitializeEx(&SerialPortInfo, 0, 0);
+        if (!KdPortInitializeEx(&SerialPortInfo, 0, 0))
+        {
+            KdpDebugMode.Serial = FALSE;
+            return;
+        }
 
         /* Register as a Provider */
         InsertTailList(&KdProviders, &DispatchTable->KdProvidersList);