Update databases/mysq5[67] ports to latest newly realesed version.

[mmokhi]

Summary

This patch updates mysql5[67] ports.
No-longer-needed patches deleted, and some patches revised.

mysql80 also has a newer version, but building from source suffers a problem that I'm working to fix
(linker error, symbol relocation. needs -fPIC flag on compiler I guess)
which seems to be upstream issue (yeah, they already warned about such issues on mysql80 😄 )

Test Plan

portlint fine.
poudriere builds fine.
runs fine.