Change log for ISC_DHCP

Date Changes
2024-11-27 Bug-Fix:
- Changed mapping for host from principal.hostname to target.asset.hostname.
- Mapped pid go target.process.pid.
- Mapped process to target.application.
- Mapped via to principal.ip and principal.asset.ip.
- Mapped ipaddress to principal.ip and principal.asset.ip.
- Mapped macaddress to principal.mac and principal.asset.mac.
2024-01-29 Enhancement:
- Added Grok patterns to parse dropped logs.
2023-12-29 Enhancement:
- Added Grok patterns to match new log format.
- If network.dhcp.ciaddr is not set, set metadata.event_type to STATUS_UPDATE.