Possible bug in Makefile when executing curl-config

I believe there may be a bug in the Makefile introduced by the following commit:

https://github.com/git/git/commit/23c4bbe28e61974577164db09cbd1d1c7e568ca4

The commit was merged in 2.20.0:

* The way -lcurl library gets linked has been simplified by taking
   advantage of the fact that we can just ask curl-config command how.

Unfortunately it assumes that curl-config is in the path which is not always the case. When using "--with-curl=/path/to/curl" in the configure command, the path to the actual curl-config executable is ignored and the build fails around here:

    CC http-fetch.o
make: curl-config: Command not found
    LINK git-http-fetch
http.o: In function `fill_active_slots':
/tmp/git-2.21.0/http.c:1385: undefined reference to `curl_easy_cleanup'
.

We were able to workaround this by forcing the correct path into the make env:

make CURL_LDFLAGS="$(/path/to/curl/curl-config --libs)".

I reproduced the problem in the latest version 2.22.0.

Thanks, Adam