patch 8.2.3375: using uninitialized memory

Problem:    Using uninitialized memory.
Solution:   Initialize textprop_save_len.

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3375,
 /**/
     3374,
 /**/