patch 8.1.0824: SunOS/Solaris has a problem with ttys

Problem:    SunOS/Solaris has a problem with ttys.
Solution:   Add mch_isatty() with extra handling for SunOS. (Ozaki Kiichi,
            closes #3865)
diff --git a/src/version.c b/src/version.c
index b952291..ddf9b14 100644
--- a/src/version.c
+++ b/src/version.c
@@ -788,6 +788,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    824,
+/**/
     823,
 /**/
     822,