Deleted NDK build from build.tmpl.gradle

The NDK build part is carried out elsewhere in p4a (as it was with ant)

Author: inclement

pythonforandroid/bootstraps/sdl2_gradle/build/templates/build.tmpl.gradle

@@ -43,12 +43,6 @@ android {
 	}
     {%- endif %}
 
-	externalNativeBuild {
-		ndkBuild {
-			path './jni/Android.mk'
-		}
-	}
-
 	buildTypes {
 		debug {
 		}
@@ -59,6 +53,12 @@ android {
 		}
 	}
 
+    sourceSets {
+        main {
+            jniLibs.srcDir 'libs' 
+            }
+        }
+
 }
 
 dependencies {