patch 8.2.4070: using uninitialized memory when reading empty file

Problem:    Using uninitialized memory when reading empty file.
Solution:   Check for empty file before checking for NL. (Dominique Pellé,
            closes #9511)

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4070,
 /**/
     4069,
 /**/