This Bazel repository facilitates building BoringSSL with the FIPS validated module BoringCrypto, which can then be used in Tink. Note that this gives no guarantee that you use BoringSSL in a FIPS compliant manner when used. It is strongly recommended to read the official security policy for BoringCrypto.
To build Tink with BoringCrypto use --override_module=boringssl=third_party/boringssl_fips, with Bazel module, and --override_repository=boringssl=third_party/boringssl_fips. Tink then offers a FIPS-only mode which will restrict the usage to algorithms which are FIPS approved and utilize the BoringCrypto module.