Two questions there:
1) What does uboot 2016 support
2) can you boot LVM
Now on the first, from:
https://archlinuxarm.org/packages/arm/uboot-nsa325/files/PKGBUILD you can see where the source came from. The original release isn't any more on git, but is probably built from, e.g.:
https://github.com/moonman/u-boot/blob/2016.09/configs/nsa325_defconfigThat shows whats was configured when the nsa 325 uboot 2016.09 was configured. So shows you what you have.
Now can you boot LVM, well I don't have a definitive answer. but if you look at the current uboot source filesystem support:
https://gitlab.denx.de/u-boot/u-boot/-/tree/master/fsAnd you don't see support for LVM. So it seems unlikely that moonman 2016 branch has LVM. Note this is what the source is, typically not all these options are defined in the config file, which is why you need to look at that and see what is included ...
[edit: and checking that nsa325_defconfig file, and its just minimal. IIRC you then need to look at uboot source code to see what config files it pulls in, e.g. what the basic file is before the nsa325 modification. I've done this in the past, so know its possible, but don't recall the details.]