add freefilter

freefilter.c

@@ -0,0 +1,15 @@
+#include "ldap.h"
+#include <stdlib.h>
+
+void freefilter(struct Filter* f) {
+  if (f) {
+    while (f->a) {
+      struct AttributeList* a=f->a->next;
+      free(f->a);
+      f->a=a;
+    }
+    if (f->x) freefilter(f->x);
+    if (f->next) freefilter(f->next);
+    free(f);
+  }
+}