Fixed (not) saving the 'cam.data' file in case VDR stops early during startup due to some error

HISTORY

@@ -9322,3 +9322,5 @@ Video Disk Recorder Revision History
 - Updated the Ukrainian OSD texts (thanks to Yarema Aka Knedlyk).
 - Fixed processing SVDRP client responses in case the caller doesn't want the actual
   response strings (reported by Johann Friedrichs).
+- Fixed (not) saving the 'cam.data' file in case VDR stops early during startup due to
+  some error.

ci.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: ci.c 4.20 2018/02/03 12:55:03 kls Exp $
+ * $Id: ci.c 4.21 2018/03/19 16:37:03 kls Exp $
  */
 
 #include "ci.h"
@@ -2993,6 +2993,8 @@ void cChannelCamRelations::Load(const char *FileName)
 
 void cChannelCamRelations::Save(void)
 {
+  if (!*fileName)
+     return;
   cMutexLock MutexLock(&mutex);
   struct stat st;
   if (stat(fileName, &st) == 0) {