Fix node daemon log file permissions

The creation of the log file for the node daemon lacks the mode
parameter, so after applying the current umask, the file got 0700
permissions. Restrict this to the correct 0600.

Reviewed-by: schreiberal

daemons/ganeti-noded

@@ -592,7 +592,7 @@ def createDaemon():
       os.close(fd)
     except OSError: # ERROR, fd wasn't open to begin with (ignored)
       pass
-  os.open(REDIRECT_TO, os.O_RDWR|os.O_CREAT|os.O_APPEND) # standard input (0)
+  os.open(REDIRECT_TO, os.O_RDWR|os.O_CREAT|os.O_APPEND, 0600)
   # Duplicate standard input to standard output and standard error.
   os.dup2(0, 1)     # standard output (1)
   os.dup2(0, 2)     # standard error (2)