This update for net-snmp fixes the following issues:

Update to net-snmp-5.9.4 (bsc#1214364).

-   libsnmp:

      - Remove the SNMP_SWIPE_MEM() macro Remove this macro since it is not
        used in the Net-SNMP code base.
      - DISPLAY-HINT fixes
      - Miscellanious improvements to the transports
      - Handle multiple oldEngineID configuration lines
      - fixes for DNS names longer than 63 characters

-   agent:

      - Added a ignoremount configuration option for the HOST-MIB
      - disallow SETs with a NULL varbind
      - fix the --enable-minimalist build

-   apps:

      - snmpset: allow SET with NULL varbind for testing
      - snmptrapd: improved MySQL logging code

-   general:

      - configure: Remove -Wno-deprecated as it is no longer needed
      - miscellanious ther bug fixes, build fixes and cleanups

- Re-add support for hostname netgroups that was removed accidentally and
  previously added with FATE#316305 (bsc#1207697).
  '@hostgroup' can be specified for multiple hosts
- Hardening systemd services setting "ProtectHome=true" caused home directory
  size and allocation to be listed incorrectly (bsc#1206044).