Avoid case in ca.c fix.

apps/apps.h

diff --git a/apps/apps.h b/apps/apps.h
index 6b7ff55..bcf597f 100644
--- a/apps/apps.h
+++ b/apps/apps.h
@@ -294,6 +294,9 @@
 int save_index(const char *dbfile, const char *suffix, CA_DB *db);
 int rotate_index(const char *dbfile, const char *new_suffix, const char *old_suffix);
 void free_index(CA_DB *db);
+#define index_name_cmp_noconst(a, b) \
+	index_name_cmp((const CSTRING *)CHECKED_PTR_OF(STRING, a), \
+	(const CSTRING *)CHECKED_PTR_OF(STRING, b))
 int index_name_cmp(const CSTRING *a, const CSTRING *b);
 int parse_yesno(const char *str, int def);