Keystore 2.0: Refactor permissions. 4/5

Remove obsolete constructor functions for permissions.

Test: keystore2_test
Bug: 203555519
Change-Id: I4ff3ff91d8a5dcca99db02ddbd5894c91c405389
diff --git a/keystore2/src/service.rs b/keystore2/src/service.rs
index b35fe36..c6d466d 100644
--- a/keystore2/src/service.rs
+++ b/keystore2/src/service.rs
@@ -274,7 +274,7 @@
                 if let Some(selinux::Error::PermissionDenied) =
                     e.root_cause().downcast_ref::<selinux::Error>()
                 {
-                    check_keystore_permission(KeystorePerm::list())
+                    check_keystore_permission(KeystorePerm::List)
                         .context("In list_entries: While checking keystore permission.")?;
                     if namespace != -1 {
                         k.nspace = namespace;