add OWNERS file to audio, media and usb services

Added:
 services/core/java/com/android/server/audio/OWNERS
 services/core/java/com/android/server/media/OWNERS
 services/usb/OWNERS

Test: make
Change-Id: I292c3acbfa4163607ce5b9a440ad4d56406fbf9d
diff --git a/services/usb/OWNERS b/services/usb/OWNERS
new file mode 100644
index 0000000..7897a0c
--- /dev/null
+++ b/services/usb/OWNERS
@@ -0,0 +1,4 @@
+badhri@google.com
+elaurent@google.com
+moltmann@google.com
+zhangjerry@google.com