Update android build scripts.

scripts/android/finish_boost.sh

@@ -1,9 +1,9 @@
-# /bin/bash
+#!/bin/sh
 
-WORKDIR=/opt/android
 ARCH=$1
-PREFIX="${WORKDIR}/prefix_${ARCH}"
-BOOST_SRC_DIR=$WORKDIR/boost_1_68_0
+PREFIX=$2
+BOOST_SRC_DIR=$3
 
 cd $BOOST_SRC_DIR
+
 ./b2 --build-type=minimal link=static runtime-link=static --with-chrono --with-date_time --with-filesystem --with-program_options --with-regex --with-serialization --with-system --with-thread --with-locale --build-dir=android --stagedir=android toolset=clang threading=multi threadapi=pthread target-os=android -sICONV_PATH=${PREFIX} install