unbound: fix check for libressl-2.2.2.

Since 2.2.2, LibreSSL uses an indirect macro to define
LIBRESSL_VERSION_TEXT, breaking the check in unbound's configure.

Without this, reallocarray is used inspite of no prototype
declaration, thus the return value of realloc will be truncated to
32-bit which results in immediate segfault on 64-bit architectures.

Closes #2232.

srcpkgs/unbound/template

@@ -1,7 +1,7 @@
 # Template file for 'unbound'
 pkgname=unbound
 version=1.5.4
-revision=2
+revision=3
 build_pie=yes
 build_style=gnu-configure
 configure_args="--with-libevent --with-conf-file=/etc/unbound/unbound.conf
@@ -19,6 +19,10 @@ homepage="http://unbound.net/"
 distfiles="http://unbound.net/downloads/${pkgname}-${version}.tar.gz"
 checksum=a1e1c1a578cf8447cb51f6033714035736a0f04444854a983123c094cc6fb137
 
+post_extract() {
+	sed -i 's/OPENSSL_VERSION_TEXT/_VERSION_TEXT/g' configure
+}
+
 post_install() {
 	vsconf doc/example.conf unbound.conf
 	vinstall ${FILESDIR}/unbound.conf 644 etc/unbound