Update CMakeLists.txt for macos installing

[cxwx]

for #390

[lukasmerten]

Can someone of the Mac users quickly check this? Looks in general fine to me, but I cannot test it.

[rafaelab]

Thanks, @cxwx
But this doesn't work for me. I get the error message

CMake Error at /opt/homebrew/Cellar/cmake/3.25.2/share/cmake/Modules/FindPkgConfig.cmake:663 (message):
  pkg-config tool not found
Call Stack (most recent call first):
  /opt/homebrew/Cellar/cmake/3.25.2/share/cmake/Modules/FindPkgConfig.cmake:829 (_pkg_check_modules_internal)
  CMakeLists.txt:230 (pkg_check_modules)

I also fail to see the underlying logic for requiring profiler, as this is not needed to run CRPropa.
After some quick search in google this problem (#390) seems to be related to Google performance tools, which is also not a requirement for CRPropa. According to this discussion, this happens when gperf is installed via brew, so it doesn't seem to be a general problem.

[lukasmerten]

I close this PR for now. If you, @cxwx, think it is still relevant, please reopen this or a new PR.