API Change: Do not delete remanent data on SET_CONFIGURATION_PARAMETERS_REQ with a changed configuration

Currently, when we receive packet SET_CONFIGURATION_PARAMETERS_REQ, we checksum it and compare with the persistently stored checksum of the previous such packet.
If checksums are equal, i.e. if the same packet has been received again, we apply the remanent data, otherwise we delete the remanent data.

With net90/GCI, this behavior changes as follows:

• Checksumming is removed, remanent data is _not_ deleted on SET_CONFIGURATION_PARAMETERS_REQ
• Instead, remanent data always has to be deleted explicitly with the HIL_DELETE_CONFIG_REQ, which also deletes the stored configuration (e.g. due to CIP Identity Reset Type 1)
• The remanent data, unless deleted explicitly, is always applied on top of the received configuration (this happens in HIL_CHANNEL_INIT_REQ)

Justification:

• Consistency with other stacks
• Choice of packet set (SetConfig vs. Extended) and remanent data storage (either by host or by stack) can become independent concepts (currently under discussion)
• Checksumming to distinguish SetConfig-packets has a chance of failure, although with very low probability

Action items:

• Implement behavior for eip_gci for netX90/eCos
• Adapt specific AP task accordingly
• Adapt API reference

 - Mention changes in porting instructions