buildroot

boost: bump to version 1.66.0

Drop the metaparse module as it is header only library now. No need for
legacy handling as the module is available unconditionally in Boost.

Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>