patch 8.2.3386: using uninitialized memory

Problem:    Using uninitialized memory.
Solution:   Initialize the rm_ic field. (Dominique Pellé, closes #8800)
diff --git a/src/indent.c b/src/indent.c
index 99951c8..f4c3982 100644
--- a/src/indent.c
+++ b/src/indent.c
@@ -953,6 +953,7 @@
 				   RE_MAGIC + RE_STRING + RE_AUTO + RE_STRICT);
 	if (regmatch.regprog != NULL)
 	{
+	    regmatch.rm_ic = FALSE;
 	    if (vim_regexec(&regmatch, line, 0))
 	    {
 		if (wp->w_briopt_list > 0)