Support fabric pin physical location file

[tangxifan]

Motivate of the pull request

• To address an existing issue. If so, please provide a link to the issue: Output preferred sides of pins for each block in an FPGA fabric w.r.t. architecture definition  #1615
• Breaking new feature. If so, please describe details in the description part.

Describe the technical details

What is currently done? (Provide issue link if applicable)

Currently, OpenFPGA has the following limitations:

See details in #1615

What does this pull request change?

This PR improves in the following aspects:

• Added a new command write_fabric_pin_physical_location and related options, as described in Output preferred sides of pins for each block in an FPGA fabric w.r.t. architecture definition  #1615
• Add a number of testcases to the basic regression tests to validate options of the newly added command.
• Add golden copies of the output files and under CI tracking
• Updated documentation

Which part of the code base require a change

• VPR
• Tileable routing architecture generator
• OpenFPGA libraries
• FPGA-Verilog
• FPGA-Bitstream
• FPGA-SDC
• FPGA-SPICE
• Flow scripts
• Architecture library
• Cell library
• Documentation
• Regression tests
• Continous Integration (CI) scripts

Impact of the pull request

• Require a change on Quality of Results (QoR)
• Break back-compatibility. If so, please list who may be influenced.