patch 8.0.1044: warning for uninitialized variable

Problem:    Warning for uninitialized variable. (John Marriott)
Solution:   Initialize ind_pre.
diff --git a/src/ops.c b/src/ops.c
index e8308bb..6fb6947 100644
--- a/src/ops.c
+++ b/src/ops.c
@@ -2507,7 +2507,7 @@
 {
     long		ins_len, pre_textlen = 0;
     char_u		*firstline, *ins_text;
-    colnr_T		ind_pre, ind_post;
+    colnr_T		ind_pre = 0, ind_post;
     struct block_def	bd;
     int			i;
     pos_T		t1;