patch 8.1.0890: pty allocation wrong if using file for out channel

Problem:    Pty allocation wrong if using file for out channel and using null
            for in channel and null for error channel.
Solution:   Correct using use_file_for_out in condition. (Ozaki Kiichi, closes
            #3917)
diff --git a/src/version.c b/src/version.c
index a990f2c..c865fc0 100644
--- a/src/version.c
+++ b/src/version.c
@@ -784,6 +784,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    890,
+/**/
     889,
 /**/
     888,