add shell script to compile android lib

build.sh

+#!/bin/bash
+#!/bin/bash
+NDK=/home/youle/Android/Sdk/ndk/20.1.5948944
+SYSROOT=${NDK}/toolchains/llvm/prebuilt/linux-x86_64/sysroot
+PLATFORM=${NDK}/toolchains/llvm/prebuilt/linux-x86_64
+
+
+function build_armv7a
+{
+   PREFIX=$(pwd)/android-armv7a
+   CPU=armv7-a
+   ./configure-android \
+       --prefix=$PREFIX \
+       --target-os=android \
+       --arch=$CPU \
+       --enable-shared \
+       --disable-static \
+       --disable-doc \
+       --disable-ffmpeg \
+       --disable-ffplay \
+       --disable-ffprobe \
+       --disable-avdevice \
+       --disable-symver \
+       --enable-cross-compile \
+       --sysroot=$SYSROOT \
+       --cross-prefix=$PLATFORM/bin/arm-linux-androideabi- \
+       --cross-prefix-clang=$PLATFORM/bin/armv7a-linux-androideabi16- \
+       --extra-cflags="-I$SYSROOT/usr/include" \
+       --extra-ldflags="-L$SYSROOT/usr/lib"
+       $ADDITIONAL_CONFIGURE_FLAG
+       make clean
+       make -j6
+       make install
+       make distclean
+}
+
+function build_aarch64
+{
+   PREFIX=$(pwd)/android-aarch64
+   CPU=aarch64
+   ./configure-android \
+       --prefix=$PREFIX \
+       --target-os=android \
+       --arch=$CPU \
+       --enable-shared \
+       --disable-static \
+       --disable-doc \
+       --disable-ffmpeg \
+       --disable-ffplay \
+       --disable-ffprobe \
+       --disable-avdevice \
+       --disable-symver \
+       --enable-cross-compile \
+       --sysroot=$SYSROOT \
+       --cross-prefix=$PLATFORM/bin/aarch64-linux-android- \
+       --cross-prefix-clang=$PLATFORM/bin/aarch64-linux-android21- \
+       --extra-cflags="-I$SYSROOT/usr/include" \
+       --extra-ldflags="-L$SYSROOT/usr/lib"
+       $ADDITIONAL_CONFIGURE_FLAG
+       make clean
+       make -j6
+       make install
+       make distclean
+}
+
+build_armv7a
+build_aarch64
+