Add/use watchdog with standard timeout

Almost all uses of the watchdog use the same 500ms timeout, so add a new
method that assumes that.

Test: CtsKeystoreTestCases
Change-Id: Idf7852400a58ba954e4a71e5e2282734a0960072
diff --git a/keystore2/src/remote_provisioning.rs b/keystore2/src/remote_provisioning.rs
index d70fe22..cda93b3 100644
--- a/keystore2/src/remote_provisioning.rs
+++ b/keystore2/src/remote_provisioning.rs
@@ -129,6 +129,6 @@
     // by the calling function and allow for natural fallback to the factory key.
     let rpc_name = get_remotely_provisioned_component_name(security_level)
         .context(ks_err!("Trying to get IRPC name."))?;
-    let _wd = wd::watch_millis("Calling get_rkpd_attestation_key()", 500);
+    let _wd = wd::watch("Calling get_rkpd_attestation_key()");
     rkpd_client::get_rkpd_attestation_key(&rpc_name, caller_uid)
 }