* ext/fiddle/depend (build-libffi): get rid of eventually empty
target for nmake.
* ext/fiddle/extconf.rb: omit stuffs for libffi unless bundled
libffi is found and used.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48913 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* ext/fiddle/extconf.rb: configure is already in mflags, use
system instead of xsystem which requires a string, and logging
libffi configure output.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48904 b2dd03c8-39d4-4d8f-98ff-823fe69b080e