Update to primitive-0.5.2.1 (again)

This was already performed via
47d725f29376fa1be726e913cdf3dd69c46327c2

However, it was accidently reverted as a side-effect of
2b34947b60069e51abfcada9c45a6d7b590f5a2b

Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>