Revert `MRUBY_TARGET` mechanism; ref #5096

* In explanation of mruby, the expression `build_config.rb` is frequently
  used including official documents, so I think that it will not make sense
  if the file is no longer used.
* The `MRUBY_TARGET` mechanism seems to have little improvement, so I don't
  think it should be changed to avoid unnecessary confusion.
* `MRUBY_TARGET` and `MRuby.targets` represent somewhat different things,
  so using the same term "target" is a bit confusing.

The mechanism that can be written short when using a file under
`build_config` (renamed from `target`) directory remains
(`build_config/${MRUBY_CONFIG}.rb` is used if the path specified
in `MRUBY_CONFIG` doesn't exist).

1 files changed, 0 insertions, 26 deletions

diff --git a/target/host-debug.rb b/target/host-debug.rb
deleted file mode 100644
index ad4106065..000000000
--- a/target/host-debug.rb
+++ /dev/null
@@ -1,26 +0,0 @@
-MRuby::Build.new('host') do |conf|
-  # load specific toolchain settings
-
-  # Gets set by the VS command prompts.
-  if ENV['VisualStudioVersion'] || ENV['VSINSTALLDIR']
-    toolchain :visualcpp
-  else
-    toolchain :gcc
-  end
-
-  enable_debug
-
-  # include the default GEMs
-  conf.gembox 'full-core'
-
-  # C compiler settings
-  conf.cc.defines = %w(MRB_ENABLE_DEBUG_HOOK MRB_NO_BOXING)
-
-  # Generate mruby debugger command (require mruby-eval)
-  conf.gem :core => "mruby-bin-debugger"
-
-  # test
-  enable_test
-  # bintest
-  enable_bintest
-end