Our internal repository was changed from phdl to ghdl. Update the
adi_env.tcl scripts and other scripts, which depends on the $ad_ghdl_dir
variable. This way the tools will see all the internal IPs too.
If the ADI_HDL_DIR or ADI_PHDL_DIR are set on Windows platforms, an
invalid TCL character (e.g. backslash) may be used as a file separator,
causing issues with the build / library scripts.
Normalize the paths before using them as global TCL variables.