thttpd: update checksum, enable build_pie.

Diff verified against MacPorts tarball.

srcpkgs/thttpd/template

@@ -1,21 +1,22 @@
 # Template file for 'thttpd'
 pkgname=thttpd
 version=2.26
-revision=2
+revision=3
 replaces="runit-void<20141013_2"
 build_style=gnu-configure
+build_pie=yes
 short_desc="Tiny/turbo/throttling HTTP server"
 maintainer="Juan RP <xtraeme@gmail.com>"
 license="BSD"
 homepage="http://www.acme.com/software/thttpd/"
 distfiles="http://www.acme.com/software/thttpd/thttpd-${version}.tar.gz"
-checksum=15b3f6c60f854061e333227e9ea9ff789d34a092c9365690a8c0d3ecfc85cbb7
+checksum=4693d7c421fe1bd25553a8891cbb447d2bab3e0df01c029dadd79596b9bdb4c5
 
 pre_configure() {
 	sed "s,-o bin -g bin,,g" -i Makefile.in
 }
-pre_build() {
-	export LD=$CC
+do_build() {
+	make ${makejobs} CC=$CC LD=$CC CCOPT="$CFLAGS -D_DEFAULT_SOURCE"
 }
 do_install() {
 	vmkdir usr/bin