doc: improved building doc for Android

PR-URL: #44166
Reviewed-By: Feng Yu <F3n67u@outlook.com>
Reviewed-By: Akhil Marsonya <akhil.marsonya27@gmail.com>

BUILDING.md

@@ -37,7 +37,7 @@ file a new issue.
       * [Option 1: Manual install](#option-1-manual-install)
       * [Option 2: Automated install with Boxstarter](#option-2-automated-install-with-boxstarter)
     * [Building Node.js](#building-nodejs-2)
-  * [Android/Android-based devices (e.g. Firefox OS)](#androidandroid-based-devices-eg-firefox-os)
+  * [Android](#android)
 * [`Intl` (ECMA-402) support](#intl-ecma-402-support)
   * [Build with full ICU support (all locales supported by ICU)](#build-with-full-icu-support-all-locales-supported-by-icu)
     * [Unix/macOS](#unixmacos)
@@ -647,22 +647,25 @@ To test if Node.js was built correctly:
 > Release\node -e "console.log('Hello from Node.js', process.version)"
 ```
 
-### Android/Android-based devices (e.g. Firefox OS)
+### Android
 
 Android is not a supported platform. Patches to improve the Android build are
 welcome. There is no testing on Android in the current continuous integration
 environment. The participation of people dedicated and determined to improve
 Android building, testing, and support is encouraged.
 
 Be sure you have downloaded and extracted
-[Android NDK](https://developer.android.com/tools/sdk/ndk/index.html) before in
+[Android NDK](https://developer.android.com/ndk) before in
 a folder. Then run:
 
 ```console
-$ ./android-configure /path/to/your/android-ndk
-$ make
+$ source ./android-configure /path/to/your/android-ndk target_arch android_sdk_version
+$ make -j4
 ```
 
+The Android SDK version should be at least 24 (Android 7.0) and the target
+architecture supports \[arm, arm64/aarch64, x86, x86\_64].
+
 ## `Intl` (ECMA-402) support
 
 [Intl](https://github.com/nodejs/node/blob/HEAD/doc/api/intl.md) support is