[libxml2] Fix pointer comparison warnings on 64-bit Windows

[Nick Wellnhofer <nwellnhof src gnome org>]

commit a4864c2f98f2a093402e6a4bb14a10af45025f40
Author: J. Peter Mugaas <jpmugaas suddenlink net>
Date:   Sat Oct 21 14:01:10 2017 +0200

    Fix pointer comparison warnings on 64-bit Windows

 nanoftp.c  |    2 +-
 nanohttp.c |    4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/nanoftp.c b/nanoftp.c
index 4458497..54fa026 100644
--- a/nanoftp.c
+++ b/nanoftp.c
@@ -901,7 +901,7 @@ xmlNanoFTPConnect(void *ctx) {
            __xmlIOErr(XML_FROM_FTP, 0, "getaddrinfo failed");
            return (-1);
        }
-       if (tmp->ai_addrlen > sizeof(ctxt->ftpAddr)) {
+       if ((size_t)tmp->ai_addrlen > sizeof(ctxt->ftpAddr)) {
            if (result)
                freeaddrinfo (result);
            __xmlIOErr(XML_FROM_FTP, 0, "gethostbyname address mismatch");
diff --git a/nanohttp.c b/nanohttp.c
index d7bc013..9cd2292 100644
--- a/nanohttp.c
+++ b/nanohttp.c
@@ -1088,7 +1088,7 @@ xmlNanoHTTPConnectHost(const char *host, int port)
 
        for (res = result; res; res = res->ai_next) {
            if (res->ai_family == AF_INET) {
-               if (res->ai_addrlen > sizeof(sockin)) {
+               if ((size_t)res->ai_addrlen > sizeof(sockin)) {
                    __xmlIOErr(XML_FROM_HTTP, 0, "address size mismatch\n");
                    freeaddrinfo (result);
                    return INVALID_SOCKET;
@@ -1098,7 +1098,7 @@ xmlNanoHTTPConnectHost(const char *host, int port)
                addr = (struct sockaddr *)&sockin;
 #ifdef SUPPORT_IP6
            } else if (have_ipv6 () && (res->ai_family == AF_INET6)) {
-               if (res->ai_addrlen > sizeof(sockin6)) {
+               if ((size_t)res->ai_addrlen > sizeof(sockin6)) {
                    __xmlIOErr(XML_FROM_HTTP, 0, "address size mismatch\n");
                    freeaddrinfo (result);
                    return INVALID_SOCKET;