The good news is, it is not related to hardware (any devices that can run Lollipop should be okay). However, the bad (or also good?) news is, it depends on the Lollipop ROM (stock or custom); if the developers decided to implement this (optional) feature.
Regarding CyanogenMod ROM, it seems that starting from CM11S 38R, it fulfills the condition to take RAW image.
Otherwise, you can check if your device supports those features using Manual Camera Compatibility.
From Camera FV-5's FAQ,
[LOLLIPOP] I have Android 5 Lollipop, but I cannot see none of the cool features announced for Android 5 (manual focus, RAW, manual exposure time...).
Camera FV-5 requires that the phone actually implements those features. Android 5 Lollipop (the OS) brings the possibility for manufacturers to implement those features, and applications to implement those. However, Google left all these features optional for manufacturers, and most of them that are currently updating their existing phones to Lollipop are not implementing them in order to rush an update to the market. From the equation, Camera FV-5 implements everything needed to use those features, Android Lollipop brings developers the possibility implement those features, but if you are not able to use them is because your manufacturer didn't actually implement their part on their devices: RAW support requires the manufacturer to update the camera driver (for instance).
Currently the features described here are supported on the following devices at the beginning:
- LG Nexus 5.
- Motorola Nexus 6.