beckham: Add IModManager to VINTF manifest

Change-Id: Ia4bdd85fa116aa62121b5b1f7218402774579f89

motomods.xml

 <manifest version="1.0" type="device">
+    <hal format="hidl">
+        <name>com.motorola.mod</name>
+        <transport>hwbinder</transport>
+        <version>1.0</version>
+        <interface>
+             <name>IModManager</name>
+             <instance>default</instance>
+         </interface>
+    </hal>
     <hal format="hidl">
         <name>motorola.hardware.audio.eqservice</name>
         <transport>hwbinder</transport>