As far as I'm aware, HSBC has its own lounge in IST Ataturk airport (administered by the bank ISO using a lounge like PP, etc.). Had been there once, it's spacious (only 3-4 people when I were there at daytime) with good toilet but average F&B.

The 'HSBC lounge' at HKG airport is basically their branch, but they offer several rooms (conference rooms?) as resting spaces (not sure if they provide food).

To me personally, compliementary access to DOH lounge is god bless, as the terminal is soooooo crowded during peak times. I truly feel the benefit of Premier when I showed my Premier CC and then get access into the lounge