target/sim: Add VCS simulation flow

[CyrilKoe]

This required this change:
AXI : pulp-platform/axi@6879518

• cheshire_pkg.sv
  • VCS: Support for parameter of type 'DefaultMapEntry' inside 'Function' is not yet implemented
• vip_cheshire_soc.sv
  • @(negedge rst_n) is not detected by VCS as rst_n is de-asserted at delta 0.
  • streams require explicit cast to string
  • concatenation of interfaces using { } is not in the standard

TODO:

• Get axi_pkg: Add iomsb to avoid underflow in array lengths axi#355 or equivalent merged
• Update Bender ref to AXI release with fix above