community/clamsmtp: enable on s390x

Related commit: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/include/uapi/linux/libc-compat.h?id=c0bace798436bca0fdc221ff61143f1376a9c3de

> This can fix symbol collisions for them, as long as the
> libc headers are included before the uapi headers

community/clamsmtp/APKBUILD

@@ -2,15 +2,16 @@
 # Maintainer: Carlo Landmeter <clandmeter@alpinelinux.org>
 pkgname=clamsmtp
 pkgver=1.10
-pkgrel=21
+pkgrel=22
 pkgdesc="An SMTP Virus Filter"
 url="http://thewalter.net/stef/software/clamsmtp/"
-arch="all !s390x"
+arch="all"
 license="BSD-3-Clause"
 install="$pkgname.pre-install $pkgname.pre-upgrade $pkgname.post-upgrade"
 subpackages="$pkgname-doc $pkgname-openrc"
 source="https://deb.debian.org/debian/pool/main/c/clamsmtp/clamsmtp_$pkgver.orig.tar.gz
 	socklen_t.patch
+	linux-headers.patch
 	clamsmtpd.confd
 	clamsmtpd.initd
 	"
@@ -52,6 +53,7 @@ package() {
 sha512sums="
 f28e2c1d78c965245d8d7a8810fbeb11d41e40383eba2e8fca500f94c2e4b8d9a2c0b9e4e8e967965bf50266968e0b9549fb62369f37724350a20174c89a044b  clamsmtp_1.10.orig.tar.gz
 c6363d3921f496df922d406b7bd572432e1e72bca56ec0e3a49f87998a270bf1a47f1a5fb49743a61245477e6cd9fa305f9b2d5e84eb5fd62c337719e6022352  socklen_t.patch
+a4b76ba69ab07487edc5d862cbee514f581d71d872c3388e5870b5c6bf98cd197931421b35864a73411deed78684f3fe283af018e8b22f6fc9cabcc8828a7e22  linux-headers.patch
 007b948a11ab4c8da737328d2088abd5b66dc7f83bf1b8bcb26a5deb639864e77553b7e7434139ddb8a916fe39beb4aabb35f766ce96274449b414268703a6ee  clamsmtpd.confd
 2540bcafa866249cd63cb961c4d589eca900e9d1bedfc06c5ae890118fd9e49f1bd126e6dc23d1d953cc1038b390a2a736b67032e9fb33e70227887a6cbc4a5c  clamsmtpd.initd
 "

community/clamsmtp/linux-headers.patch

@@ -0,0 +1,24 @@
+Patch-Source: http://thewalter.net/git/cgit.cgi/clamsmtp/commit/?h=linux-build-fixes&id=7f2b835dd5db4dcfdbe88e238c89084785724925
+--- a/common/smtppass.c
++++ b/common/smtppass.c
+@@ -59,16 +59,15 @@
+ #include <time.h>
+ 
+ #include "usuals.h"
+-
+-#ifdef LINUX_TRANSPARENT_PROXY
+-#include <linux/netfilter_ipv4.h>
+-#endif
+-
+ #include "compat.h"
+ #include "sock_any.h"
+ #include "stringx.h"
+ #include "sppriv.h"
+ 
++#ifdef LINUX_TRANSPARENT_PROXY
++#include <linux/netfilter_ipv4.h>
++#endif
++
+ /* -----------------------------------------------------------------------
+  *  STRUCTURES
+  */