databases/mysql{84,97}: Install man pages, clean up dependencies
Re-enable installation of the man pages shipped in the source tarball
and register them in pkg-plist, split between the client and server
packages. Same approach as databases/mysql80-client in PR 279234.
Rework the dependencies based on actual linkage: libfido2 is only used
by the client, curl, icu and liblz4 only by the server. Drop libhidapi
entirely, it is a transitive dependency of libfido2.
While here, fix the CONFLICTS_INSTALL pattern of mysql84-client not
matching mysql80-client and update the mysql84 pkg-message.
Sponsored by: Netzkommune GmbH