net/ntp: Replace the workaround from 98e34e8e2557 with a patch from upstream

43537eb9c3 circumvented an upstream patch which caused an IPv6
pool regresson. This patch removes the circumvention and replaces
it with an upstream patch planned for the new release of ntp.

Obtained from:	src bc02e6558720
MFH:		2025Q1

net/ntp/Makefile

@@ -1,6 +1,6 @@
 PORTNAME=	ntp
 PORTVERSION=	4.2.8p18
-PORTREVISION=	2
+PORTREVISION=	3
 CATEGORIES=	net
 MASTER_SITES=	http://www.eecis.udel.edu/~ntp/ntp_spool/ntp4/ntp-4.2/ \
 		http://archive.ntp.org/ntp4/ntp-4.2/

net/ntp/files/patch-ntpd_ntp__io.c

@@ -1,6 +1,17 @@
 --- ntpd/ntp_io.c.orig	2024-05-07 04:21:17.000000000 -0700
-+++ ntpd/ntp_io.c	2025-02-18 19:31:18.434141000 -0800
-@@ -3205,7 +3205,7 @@
++++ ntpd/ntp_io.c	2025-02-18 19:38:16.412031000 -0800
+@@ -1486,9 +1486,7 @@
+ 
+ 	if (IS_IPV6(psau)) {
+ 		p6addr = &psau->sa6.sin6_addr;
+-		if (   IN6_IS_ADDR_LINKLOCAL(p6addr)
+-		    || IN6_IS_ADDR_SITELOCAL(p6addr)) {
+-
++		if (IN6_IS_ADDR_LINKLOCAL(p6addr)) {
+ 			return TRUE;
+ 		}
+ 	} else if (IS_IPV4(psau)) {
+@@ -3205,7 +3203,7 @@
  	}
  
  	do {

net/ntp/files/patch-ntpd_ntp_proto.c

@@ -1,18 +0,0 @@
---- ntpd/ntp_proto.c.orig	2024-05-07 04:21:28.000000000 -0700
-+++ ntpd/ntp_proto.c	2024-12-23 14:40:06.218503000 -0800
-@@ -471,6 +471,7 @@
- 		return;
- 	}
- 
-+#if 0
- 	/* [Bug 3851] drop pool servers which can no longer be reached. */
- 	if (MDF_PCLNT & peer->cast_flags) {
- 		if (   (IS_IPV6(&peer->srcadr) && !nonlocal_v6_addr_up)
-@@ -479,6 +480,7 @@
- 			return;
- 		}
- 	}
-+#endif
- 
- 	 /*
- 	 * In unicast modes the dance is much more intricate. It is