patch 8.2.3375: using uninitialized memory

Problem:    Using uninitialized memory.
Solution:   Initialize textprop_save_len.
diff --git a/src/version.c b/src/version.c
index 0630ae6..5211f8f 100644
--- a/src/version.c
+++ b/src/version.c
@@ -756,6 +756,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3375,
+/**/
     3374,
 /**/
     3373,