nlist: Fix pread() return value check We should check for partial reads, and not continue in those cases, as we are not retrying them, otherwise we might end up operating on uninitialized data. Reported-by: Daniel Hodson <daniel@elttam.com.au> Based-on-patch-by: Daniel Hodson <daniel@elttam.com.au> Signed-off-by: Guillem Jover <guillem@hadrons.org>