The only place GL_UNPACK_LSB_FIRST + GL_PACK_LSB_FIRST are mentioned in the OpenGL 3.2 spec is listed in tables (3.1 + 4.7). There should be a description somewhere of what effect they have.
UNPACK_LSB_FIRST is described in section 3.7.5 "Rasterization of Pixel
Rectangles" of the compatibility profile spec, and PACK_LSB_FIRST is
described (inferentially) in the last paragraph of section 4.3.3 in
that spec. I believe you have a good point about the core profile
Someone was messing with Bugzilla. Fixing fields.
The history of this was that we took BITMAP out of core profile in GL 3.2,
but didn't realize that the only uses of the *PACK_LSB_FIRST state was with
BITMAP formats, so they stayed in core. We have deprecated the state in
GL 4.3 but we're never going to remove it from core since it's conceivable
that someone is setting/getting it even though it has no functionality.