Convert all comments into "doxygen-ready" comments.

Bug: 36453077
Test: mma
Change-Id: I0b1f77dfae5d2258969e33d85ecf45401ffbdfaa
diff --git a/audio/2.0/IDevicesFactory.hal b/audio/2.0/IDevicesFactory.hal
index 0ef6bc5..6bbe7a1 100644
--- a/audio/2.0/IDevicesFactory.hal
+++ b/audio/2.0/IDevicesFactory.hal
@@ -30,7 +30,7 @@
         STUB
     };
 
-    /*
+    /**
      * Opens an audio device. To close the device, it is necessary to release
      * references to the returned device object.
      *