Revert^2 "Bump keystore2 AIDL API version 1->2"

6b96760c1be3c517d549edcb96a35798788edd27

Change-Id: I93fb064c0e8cd5a92b440daca0f417663fb3ed9e
diff --git a/keystore2/android.system.keystore2-service.xml b/keystore2/android.system.keystore2-service.xml
index 6b8d0cb..20c2fba 100644
--- a/keystore2/android.system.keystore2-service.xml
+++ b/keystore2/android.system.keystore2-service.xml
@@ -1,6 +1,7 @@
 <manifest version="1.0" type="framework">
     <hal format="aidl">
         <name>android.system.keystore2</name>
+        <version>2</version>
         <interface>
             <name>IKeystoreService</name>
             <instance>default</instance>