patch 8.1.0266: parsing Ex address range is not a separate function

Problem:    Parsing Ex address range is not a separate function.
Solution:   Refactor do_one_cmd() to separate address parsing.

src/version.c

@@ -794,6 +794,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    266,
 /**/
     265,
 /**/