Remove the plugins using snmpwalk to produce their results, as there
are three different, Perl-based implementations.
Of these, one might not work because it uses net-snmp and thus rely on
the presence of some MIB file which might not be present.
None of the plugins use Munin::SNMP and none uses multigraph
capabilities.
My plugin uses the same SNMP framework as the official plugins in
munin; these use either sh and net-snmp commands, or Net::SNMP
directly, and neither seems to be generic enough.