Add configurable redundancy

[Lynx005F]

Adds top level modules and ports for time-based redundancy e.g. protection against single event upsets.

Depends on #10 and redundancy cells PRs Redundancy Cells #25 and Redundancy Cells #26.

This changes the ports of the top level module. Newly added are:

• input logic redundancy_enable_i (switches on/off redundancy)
• output logic fault_detected_o (for a performance counter to see if faults actually occurr)
• Parameter RedundancyFeatures to choose redundancy implementation (fpnew_pkg::DEFAULT_NO_REDUNDANCY results in the same unit as before)

Testing

This version of FPNew can be error injected and analyzed for vulnerabilities to single event upsets with the itemm/error_injection branch of fpnew_tb.

Synthesis

This version of FPNew can be synthesized with the scripts in the internal gitlab for the R5SCY and CVA6 Core configurations to evaluate area overhead. Depending on the choosen implementation (not disabled ofc), redundancy add 7% - 12% of Area and increases the length of the critical path by a similar amount.

Work in Progress Points

• Adding a guard clause so redundancy_enable_i can not be set when implementation allows no redundancy
• Recalculating division max delay if it has leading / trailing pipeline registers
• Merging dependencies