Improve support for Android users on M1 machine

Summary:
This is a follow up to my previous diff. It applies the same customization for M1 users to the :ReactAndroid:hermes-engine build.

The two diffs are split so the first one can be cherry-picked into 0.68.1 if needed.

Changelog:
[Android] [Fixed] - Improve support for Android users on M1 machine

Reviewed By: mdvacca

Differential Revision: D35468658

fbshipit-source-id: c07822f6708f872456971378f44257f6c1e967ee

Author: cortinico

ReactAndroid/hermes-engine/build.gradle

@@ -101,10 +101,13 @@ android {
     compileSdkVersion 31
     buildToolsVersion = "31.0.0"
 
-    // Used to override the NDK path & version on internal CI
-    if (System.getenv("ANDROID_NDK") != null && System.getenv("LOCAL_ANDROID_NDK_VERSION") != null) {
-        ndkPath System.getenv("ANDROID_NDK")
-        ndkVersion System.getenv("LOCAL_ANDROID_NDK_VERSION")
+    // Used to override the NDK path/version on internal CI or by allowing
+    // users to customize the NDK path/version from their root project (e.g. for M1 support)
+    if (rootProject.hasProperty("ndkPath")) {
+        ndkPath rootProject.ext.ndkPath
+    }
+    if (rootProject.hasProperty("ndkVersion")) {
+        ndkVersion rootProject.ext.ndkVersion
     }
 
     defaultConfig {