* add tsim init function

* add sim device

* test wait and resume

* launch simulation thread from DPILoader

* add VTASimDPI module to handle all simulation related stuff

* test tsim init

* move exit to simdpi module

* update vta driver

* add chisel DPI module

* get back simshell

* update vta to support dpi sim

* update unittests

* add tsim to integration-conv2d test

* run resnet on tsim

* remove max-cycles

* match tsim counters with sim counters

* use env in simulator to switch between sim and tsim

* update unittest

* rollback conv2d test

* update resnet

* add stats to matrix multiply

* add stats

* print stats after assert

* update other tests

* add stats to gemm

* add return and remove unused libs

* add missing arg

* return lib

* update comments for linter

* add more comments to VTASimDPI module

* remove trailing spaces

* remove trailing spaces