buffet: Removed "owner" from localAnonymousAccessMaxRole

Final set of roles does not include owner here.

BUG=brillo:947
TEST=FEATURE=test emerge-gizmo privetd

Change-Id: I5ff11cdc7a48f99c480bb5ab357f32ce82b80003
Reviewed-on: https://chromium-review.googlesource.com/270677
Reviewed-by: Alex Vakulenko <avakulenko@chromium.org>
Commit-Queue: Vitaly Buka <vitalybuka@chromium.org>
Tested-by: Vitaly Buka <vitalybuka@chromium.org>

buffet/buffet_config.cc

diff --git a/buffet/buffet_config.cc b/buffet/buffet_config.cc
index 7a9939b..bcab1ef 100644
--- a/buffet/buffet_config.cc
+++ b/buffet/buffet_config.cc
@@ -40,8 +40,7 @@
 }
 
 bool IsValidAccessRole(const std::string& role) {
-  return role == "none" || role == "viewer" || role == "user" ||
-         role == "owner";
+  return role == "none" || role == "viewer" || role == "user";
 }
 
 }  // namespace