patch 9.1.0826: filetype: sway files are not recognized

Problem:  filetype: sway files are not recognized
Solution: detect '*.sw' files as sway filetype, include
          a filetype plugin (Riley Bruins)

References:
 https://github.com/FuelLabs/sway.

Comments taken from their syntax documentation. File extension taken
from the same documentation/GitHub's own recognition of these file types

closes: #15973

Signed-off-by: Riley Bruins <ribru17@hotmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    826,
 /**/
     825,
 /**/