build_config/no-float.rb: unify two build configurations; #5421

- stop cross building
- add more gems for tests
- add `bintest`

build_config/no-float.rb

-# Define cross build settings
-MRuby::CrossBuild.new('no-float') do |conf|
-  conf.toolchain
+MRuby::Build.new do |conf|
+  # load specific toolchain settings
+  toolchain :gcc
+
+  # include the GEM box
+  conf.gembox "stdlib"
+  conf.gembox "stdlib-ext"
+  conf.gembox "stdlib-io"
+  conf.gembox "metaprog"
+
+  conf.gem :core => 'mruby-bin-mruby'
+  conf.gem :core => 'mruby-bin-mirb'
 
   # Add configuration
   conf.compilers.each do |c|
     c.defines << "MRB_NO_FLOAT"
   end
 
-  conf.gem :core => "mruby-bin-mruby"
-
-  conf.test_runner.command = 'env'
-
   conf.enable_debug
-#  conf.enable_bintest
   conf.enable_test
+  conf.enable_bintest
 end

build_config/nofloat.rb

-MRuby::Build.new do |conf|
-  # load specific toolchain settings
-  toolchain :gcc
-
-  # include the GEM box
-  conf.gembox "stdlib"
-  conf.gembox "stdlib-ext"
-  conf.gembox "stdlib-io"
-  conf.gembox "metaprog"
-
-  conf.gem :core => 'mruby-bin-mruby'
-  conf.gem :core => 'mruby-bin-mirb'
-
-  conf.cc.defines << 'MRB_NO_FLOAT'
-
-  # Turn on `enable_debug` for better debugging
-  conf.enable_debug
-  conf.enable_test
-  conf.enable_bintest
-end