configure.tgt: Simplify, just use VTV_SUPPORTED.

gcc
2013-08-08  Benjamin Kosnik  <bkoz@rehat.com>
	    Michael Meissner <meissner@linux.vnet.ibm.com>

	* configure.tgt : Simplify, just use VTV_SUPPORTED.

gcc/libvtv
2013-08-08  Benjamin Kosnik  <bkoz@redhat.com>

	* configure.ac: Adjust to check VTV_SUPPORTED.
	* configure: Regenerated.

From-SVN: r201616