#186 CMake error on macOS when building with Fortran bindings

[OpenCoarrays Dev]

A similar bug to #163 still happens in 5.12 when building the Fortran bindings:
https://github.com/Homebrew/homebrew-core/issues/15851

This is the CMake error message I am getting:

CMake Error at cmake/modules/pkg-config.cmake:228 (string):
  string sub-command REGEX, mode REPLACE needs at least 6 arguments total to
  command.
Call Stack (most recent call first):
  cmake/modules/pkg-config.cmake:419 (pkg_config_link_flags)
  bindings/f95/CMakeLists.txt:205 (pkg_config_file)

This is a regression and did not happen in 5.11.

[OpenCoarrays Dev]

The full log of the homebrew attemted build is at https://gist.github.com/ebd2c0edfd975914ea03d6147d70f531

[OpenCoarrays Dev]

This appears to be the same as #163... I have a patch at https://gist.github.com/zbeekman/7e958baf7f3271083209caaf4b0f9af5 Please advise on how to proceed.