patch 8.2.2293: build failure with Motif

Problem:    Build failure with Motif. (Tony Mechelynck)
Solution:   Use empty_option instead of empty_options.

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2293,
 /**/
     2292,
 /**/