update support lib javadoc task to use new doclava options

as per ag/2109007
This is required only when generating the new standalone version
of the support library (instead of being part of the framework docs)

Change-Id: I50734cf0aa3c983bf7541a5ce5ae5c0474932291

diff_and_docs.gradle

@@ -124,7 +124,8 @@ task generateDocs(type: DoclavaTask, dependsOn: [configurations.doclava, generat
         if (!offlineDocs) {
             addStringOption "toroot", "/"
             addBooleanOption "devsite", true
-            addBooleanOption "androidSupportRef", true
+            addStringOption "dac_libraryroot", "android/support/"
+            addStringOption "dac_dataname", "SUPPORT_DATA"
         }
     }