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/globals.rs b/keystore2/src/globals.rs
index 7ac1038..2d5c20a 100644
--- a/keystore2/src/globals.rs
+++ b/keystore2/src/globals.rs
@@ -165,7 +165,7 @@
         (
             Box::new(|uuid, blob| {
                 let km_dev = get_keymint_dev_by_uuid(uuid).map(|(dev, _)| dev)?;
-                let _wp = wd::watch_millis("In invalidate key closure: calling deleteKey", 500);
+                let _wp = wd::watch("In invalidate key closure: calling deleteKey");
                 map_km_error(km_dev.deleteKey(blob))
                     .context(ks_err!("Trying to invalidate key blob."))
             }),
@@ -306,7 +306,7 @@
         }
     };
 
-    let wp = wd::watch_millis("In connect_keymint: calling getHardwareInfo()", 500);
+    let wp = wd::watch("In connect_keymint: calling getHardwareInfo()");
     let mut hw_info =
         map_km_error(keymint.getHardwareInfo()).context(ks_err!("Failed to get hardware info."))?;
     drop(wp);