Convert all comments into "doxygen-ready" comments.

Bug: 36453077
Test: make
Change-Id: Ic77394d4d2e1ccedba3a28230d870c5d6108bd40
diff --git a/nfc/1.0/INfcClientCallback.hal b/nfc/1.0/INfcClientCallback.hal
index a56cc09..9972ada 100644
--- a/nfc/1.0/INfcClientCallback.hal
+++ b/nfc/1.0/INfcClientCallback.hal
@@ -17,13 +17,13 @@
 package android.hardware.nfc@1.0;
 
 interface INfcClientCallback {
-    /*
+    /**
      * The callback passed in from the NFC stack that the HAL
      * can use to pass events back to the stack.
      */
     sendEvent(NfcEvent event, NfcStatus status);
 
-    /*
+    /**
      * The callback passed in from the NFC stack that the HAL
      * can use to pass incomming data to the stack.
      */