lib/: Remove off-by-one bugs in calls to strncpy(3)

lib/: Remove off-by-one bugs in calls to strncpy(3)

We're not even zeroing the last byte after this call.  This was a
completely gratuitous truncation of one byte, and the resulting
character array still wasn't guaranteed to be null terminated, because
strncpy(3) can't do that.

Just to clarify, none of these structures needed zeroing, as they are
treated as null-padded fixed-size character arrays.  Calling strncpy(3)
was actually the correct call, and the only problem was unnecessarily
truncating strings by one byte more than necessary.

Cc: Matthew House <mattlloydhouse@gmail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>