merge revision(s) 41815,41816: [Backport #8606]

	* configure.in (RUBY_DTRACE_POSTPROCESS): dtrace version SUN D 1.11
	  introduces a check in the dtrace compiler to ensure that probes
	  actually exist. If there are no probes, then the -G step will
	  fail. As this test is only being used to determine whether -G is
	  necessary (for instance, on OSX it is not), adding a real probe to
	  the conftest allows it to succeed on newer versions of dtrace.
	  Patch by Eric Saxby <sax AT livinginthepast.org> at
	  [ruby-core:55826].  [Fix GH-351], [Bug #8606].


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@41943 b2dd03c8-39d4-4d8f-98ff-823fe69b080e