Adding link to gcov depending on GCC_VERSION (#46928)
Summary:
We already link g++ and gcc to the correct version, but we do not do that for gcov, which is needed for coverage.
This PR adds a link for gcov as well.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/46928
Reviewed By: malfet
Differential Revision: D24569240
Pulled By: janeyx99
fbshipit-source-id: 4be012bff21ddae0c81339665b58324777b9304f
