patch 9.1.0829: Vim source code uses a mix of tabs and spaces

Problem:  Vim source code uses a mix of tabs and spaces
Solution: Expand tabs in sound.c, this is an experiment
          (Luca Saccarola)

closes: #15969

Signed-off-by: Luca Saccarola <github.e41mv@aleeas.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/sound.c

@@ -1,4 +1,4 @@
-/* vi:set ts=8 sts=4 sw=4 noet:
+/* vi:set ts=8 sts=4 sw=4 et:
  *
  * VIM - Vi IMproved    by Bram Moolenaar
  *

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    829,
 /**/
     828,
 /**/