update README: correct build instructions, clarify supported Verilato…

…r versions.

README.md

@@ -32,7 +32,7 @@ If you use vRTLmod in your academic work you can cite it like this:
 ## Dependencies
 Besides standard (gmake, cmake, gcc, ...)
 
-1. Verilator  - tested with v4.204 (see: https://www.veripool.org/wiki/verilator and install guide)
+1. Verilator  - tested with v4.202, v4.204, and v4.228 (see: https://www.veripool.org/wiki/verilator and install guide). Currently no support for Verilator version <4 and >4!
 2. LLVM - tested v13.0.1 built with `-D LLVM_ENABLE_PROJECTS="clang;clang-tools-extra"`
 3. Boost filesystem
 4. For Tests: Conan v<2.0, tested with 1.59.0 (`pip install --force-reinstall "conan==1.59.0"`)
@@ -46,10 +46,9 @@ Besides standard (gmake, cmake, gcc, ...)
 	[BUILD]: export VERILATOR_ROOT=<path/to/verilator/build/or/install/directory>
 ```
 
-2. **Or via CMake command line arguments:**
+2. **CMake command line arguments:**
 
 ```
-mkdir build && cd build
 cmake -S . -B build -D LLVM_DIR=<path/to/llvm/install/dir> -D VERILATOR_ROOT=<path/to/verilator/build/or/install/directory> [-D BUILD_TESTING=Off]
 cmake --build build
 ```