SSP offset

Implement additional SW offset to Measured secondary sampling point. Measured SSP OFFSET (trv_delay), can be still read from TRV_DELAY. Higher bits of trv_delay register can be used for offset and offset control.

Following options for SSP offset:

1. Use only measured value
2. Use only SW offset.
3. Use measured value + SW offset.

Addition of trv_delay and SW SSP offset will be realized inside Bus Sampling module, since shift registers for secondary sampling are implemented there.