merge revision(s) 44476: [Backport #9317]

	* configure.in: reset LDFLAGS and DLDFLAGS for opt-dir again after
	  LIBPATHFLAG and RPATHFLAG are set.  [ruby-dev:47868] [Bug #9317]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@45017 b2dd03c8-39d4-4d8f-98ff-823fe69b080e