Log Message:
devel/ruby-ffi: update to 1.15.0

1.15.0 / 2021-03-05

Fixed:

* Fix MSVC build
* Fix async callbacks in conjunction with fork(). #884

Added:

* Allow to pass callbacks in varargs. #885
* Name the threads for FFI callback dispatcher and async thread calls for
  easier debugging.  #883 The name can be retrieved by Thread.name and is
  shown by Thread.list.inspect etc.  Even gdb shows the thread name on
  supported operating systems.
* Add types.conf for powerpc64le-linux
* Add types.conf for riscv64-linux
* More release automation of ffi gems

Changed:

* Switch from rubygems-tasks to bundler/gem_helper

Removed:

* Remove unused VariadicInvoker#init