Rename struct rtldsa_vlan_info to struct otto_vlan_info and update
all references to match the otto_vlan_ namespace.
No functional changes intended.
Assisted-by: ChatGPT (OpenAI GPT-6 Astra)
Link: https://github.com/openwrt/openwrt/pull/25817
Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>