patch 8.1.2090: not clear why channel log file ends

Problem:    Not clear why channel log file ends.
Solution:   Add a "closing" line.

Author: brammool

src/channel.c

@@ -141,7 +141,13 @@ ch_logfile(char_u *fname, char_u *opt)
     FILE   *file = NULL;
 
     if (log_fd != NULL)
+    {
+	if (*fname != NUL)
+	    ch_log(NULL, "closing, opening %s", fname);
+	else
+	    ch_log(NULL, "closing");
 	fclose(log_fd);
+    }
 
     if (*fname != NUL)
     {

src/version.c

@@ -757,6 +757,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2090,
 /**/
     2089,
 /**/