serf: fix undefined version ERR_GET_FUNC

The function has been removed from openssl 3.  Annoyingly enough the
build of serf doesn't fail even with this function being undefined, it
is just reported as a warning:

buckets/ssl_buckets.c:1329:24: warning: implicit declaration of function 'ERR_GET_FUNC' is invalid in C99 [-Wimplicit-function-declaration]
                       ERR_GET_FUNC(err),
                       ^

but trying to use any program linked against libserf.so later fails.

packages/serf/build.sh

@@ -3,7 +3,7 @@ TERMUX_PKG_DESCRIPTION="High performance C-based HTTP client library"
 TERMUX_PKG_LICENSE="Apache-2.0"
 TERMUX_PKG_MAINTAINER="@termux"
 TERMUX_PKG_VERSION=1.3.9
-TERMUX_PKG_REVISION=7
+TERMUX_PKG_REVISION=8
 TERMUX_PKG_SRCURL=https://archive.apache.org/dist/serf/serf-${TERMUX_PKG_VERSION}.tar.bz2
 TERMUX_PKG_SHA256=549c2d21c577a8a9c0450facb5cca809f26591f048e466552240947bdf7a87cc
 TERMUX_PKG_DEPENDS="apr, apr-util, openssl, libuuid, libexpat, zlib"

packages/serf/ssl_buckets.c.patch

@@ -0,0 +1,12 @@
+--- ../ssl_buckets.c.orig	2022-02-28 10:07:45.179525952 +0100
++++ ./buckets/ssl_buckets.c	2022-02-28 10:21:21.360065552 +0100
+@@ -1325,8 +1325,7 @@
+                 return 0;
+             }
+             else {
+-                printf("OpenSSL cert error: %d %d %d\n", ERR_GET_LIB(err),
+-                       ERR_GET_FUNC(err),
++                printf("OpenSSL cert error: %d %d\n", ERR_GET_LIB(err),
+                        ERR_GET_REASON(err));
+                 PKCS12_free(p12);
+                 bio_meth_free(biom);