MFC r310950:

MFC r310950:

MIB-II: use strlcpy when copying interface names to .ifr_name

.ifra_name is assumed to be NUL terminated; using strlcpy(3)
ensures that it's indeed NUL terminated whereas strncpy does
not.

Tested and verified as follows with a combination of ifconfig,
snmpget, and snmpset:

  % ifconfig create lo1 127.0.0.2/8
  % SNMPARGS="-v 3 -n '' -u bsnmp -A bsnmptest -l authPriv -a sha -x des -X bsnmptest localhost"
  % snmpget $SNMPARGS IF-MIB::ifAdminStatus.4
  IF-MIB::ifAdminStatus.4 = INTEGER: up(1)
  % snmpset $SNMPARGS IF-MIB::ifAdminStatus.4 i 2
  IF-MIB::ifAdminStatus.4 = INTEGER: down(2)
  % snmpget $SNMPARGS IF-MIB::ifAdminStatus.4
  IF-MIB::ifAdminStatus.4 = INTEGER: down(2)
  % snmpset $SNMPARGS IF-MIB::ifAdminStatus.4 i 1
  IF-MIB::ifAdminStatus.4 = INTEGER: up(1)
  % snmpget $SNMPARGS IF-MIB::ifAdminStatus.4
  IF-MIB::ifAdminStatus.4 = INTEGER: up(1)

CID:		1009652-1009656, 1349850

git-svn-id: svn://svn.freebsd.org/base/stable/10@312089 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f