patch 8.1.0275: 'incsearch' with :s doesn't start at cursor line

Problem:    'incsearch' with :s doesn't start at cursor line.
Solution:   Set cursor before parsing address. (closes #3318)
            Also accept a match at the start of the first line.

src/version.c

@@ -794,6 +794,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    275,
 /**/
     274,
 /**/