Update g++.dg/cpp0x/gen-attrs-{8,36,37}.C as c++11 attributes to types are ignored

The current implementation of C++11 attributes forbids them from being
applied to a type unless the type is being declared.  I forgot to
adjust g++.dg/cpp0x/gen-attrs-{8,36,37}.C that was being run only on
ia32.

Fixed thus, tested on i386-unknown-linux-gnu and
x86_64-unknown-linux-gnu against trunk.

gcc/testsuite/

	* g++.dg/cpp0x/gen-attrs-8.C: Update the test to reflect the fact
	that c++11 attributes to types are ignored for now.
	* g++.dg/cpp0x/gen-attrs-36.C: Likewise.
	* g++.dg/cpp0x/gen-attrs-37.C: Likewise

From-SVN: r192300