sed: Remove host build step

See http://lists.gnu.org/archive/html/bug-sed/2017-01/msg00001.html

packages/sed/build.sh

@@ -4,11 +4,7 @@ TERMUX_PKG_VERSION=4.3
 TERMUX_PKG_SRCURL=https://mirrors.kernel.org/gnu/sed/sed-${TERMUX_PKG_VERSION}.tar.xz
 TERMUX_PKG_SHA256=47c20d8841ce9e7b6ef8037768aac44bc2937fff1c265b291c824004d56bd0aa
 TERMUX_PKG_BUILD_IN_SRC=yes
-TERMUX_PKG_HOSTBUILD=true
 
 termux_step_post_configure () {
-	# sed uses help2man, so take man page from host build.
-	chmod u+w $TERMUX_PKG_BUILDDIR/doc/sed.1
-	cp $TERMUX_PKG_HOSTBUILD_DIR/doc/sed.1 $TERMUX_PKG_BUILDDIR/doc/sed.1
-	$TERMUX_TOUCH -d "next hour" $TERMUX_PKG_BUILDDIR/doc/sed.1
+	$TERMUX_TOUCH -d "next hour" $TERMUX_PKG_SRCDIR/doc/sed.1
 }