Prefixing BoringSSL symbols

[jedisct1]

It looks like importing boring-sys in a project that also depends on openssl-sys can cause linking errors.

In order to avoid collisions with other libraries, or other versions of BoringSSL, BoringSSL has the BORINGSSL_PREFIX_SYMBOLS CMake variable to prepend a prefix to all symbols.

Is it something that boring-sys could possibly take advantage of?

[ta3pks]

any updates on this?