requires a smi_scalar_oidlen() afterwards to set 'bo_n' to the correct
The old ber_oid_cmp() from usr.sbin/snmpd/ber.c used to iterate over
all elements of 'bo_id' and not just the first 'bo_n' ones. So calling
smi_scalar_oidlen() wasn't a requirement here. However, with the new
ober_oid_cmp() it is, since this version only iterates up to 'bo_n'