update: Use cve_is_dir() helper

Remove open coded stat() + S_ISDIR() usage with cve_is_dir() helper.

Signed-off-by: Sergey Popovich <popovich_sergei@mail.ua>

src/update.c

@@ -90,13 +90,11 @@ cve_string *get_db_path(const char *path)
         }
 
         if (mkdir(dir, mode)) {
-                struct stat st = { .st_ino = 0, };
-
                 if (errno != EEXIST) {
                         return NULL;
                 }
 
-                if (stat(dir, &st) || !S_ISDIR(st.st_mode)) {
+                if (!cve_is_dir(dir)) {
                         return NULL;
                 }
         }