This reverts commit 5ce2429a.

Reverts https://github.com/google/benchmark/pull/923
Reopens https://github.com/google/benchmark/issues/922
Fixes https://github.com/google/benchmark/issues/928
Closes https://github.com/google/benchmark/pull/930

See discussion in https://github.com/google/benchmark/issues/928
this broke pkg-config support, since there we don't account
for the suffix, nor is it trivial to do so.