IVGCVSW-2775 Adding extra step to the AndroidNN driver README for Android P

Change-Id: I85579012318e77156dc2f264c564dae86bac254b
diff --git a/README.md b/README.md
index e26523a..1da9990 100644
--- a/README.md
+++ b/README.md
@@ -31,6 +31,20 @@
 PRODUCT_PACKAGES += android.hardware.neuralnetworks@1.1-service-armnn
 </pre> `Android.mk` contains the module definition of both versions of the ArmNN driver.
 
+For Android P the vendor manifest.xml requires the Neural Network HAL information.
+```xml
+<hal format="hidl">
+    <name>android.hardware.neuralnetworks</name>
+    <transport>hwbinder</transport>
+    <version>1.1</version>
+    <interface>
+        <name>IDevice</name>
+        <instance>armnn</instance>
+    </interface>
+    <fqname>@1.1::IDevice/armnn</fqname>
+</hal>
+```
+
 4. Build Android as normal, i.e. run `make` in `<ANDROID_ROOT>`
 5. To confirm that the ArmNN driver has been built, check for driver service executable at