Bump target-level to 3.

Test: m check-vintf-all
Bug: 163419744
Change-Id: If2936b4bf1c6137ad8039fcf78216b3edf7dce77
diff --git a/manifest.xml b/manifest.xml
index fd6f383..e9cc7d9 100644
--- a/manifest.xml
+++ b/manifest.xml
@@ -1,4 +1,4 @@
-<manifest version="1.0" type="device" target-level="2">
+<manifest version="1.0" type="device" target-level="3">
     <hal format="hidl">
         <name>android.hardware.audio</name>
         <transport>hwbinder</transport>