λ build conf-pkg-config 2 failed

[Berwin2020]

Trying to install the Dream package for opam.
How can I install conf-pkg-config 2 and or pkgconf please?

The error report and message below displayed for an error report.
Please see the attached text file of the install log.
opamdream.txt

<><> Error report <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
┌─ The following actions failed
│ λ build conf-pkg-config 2
└─
The packages you requested declare the following system dependencies. Please
make sure they are installed before retrying:
system:pkgconf