BUILD: makefile: enable crypt(3) for NetBSD

Allow NetBSD to support encrypted passwords in Userlists.
diff --git a/Makefile b/Makefile
index 580cf6f..10c9ef7 100644
--- a/Makefile
+++ b/Makefile
@@ -453,8 +453,8 @@
 # NetBSD 8 and above
 ifeq ($(TARGET),netbsd)
   set_target_defaults = $(call default_opts, \
-    USE_POLL USE_TPROXY USE_THREAD USE_KQUEUE USE_ACCEPT4 USE_CLOSEFROM   \
-    USE_GETADDRINFO)
+    USE_POLL USE_TPROXY USE_LIBCRYPT USE_THREAD USE_KQUEUE USE_ACCEPT4        \
+    USE_CLOSEFROM USE_GETADDRINFO)
 endif
 
 # AIX 5.1 only