Fixup graphite/uns-*.c testcases

Fixup graphite/uns-*.c testcases

2015-07-25  Tom de Vries  <tom@codesourcery.com>

	* gcc.dg/graphite/graphite.exp: Include uns-*.c files in
	interchange_files and block_files variables.
	* gcc.dg/graphite/uns-block-1.c (main): Change signed into unsigned
	arithmetic.
	* gcc.dg/graphite/uns-interchange-12.c: Same.
	* gcc.dg/graphite/uns-interchange-14.c: Same.
	* gcc.dg/graphite/uns-interchange-15.c: Same.
	* gcc.dg/graphite/uns-interchange-9.c (foo): Same.
	* gcc.dg/graphite/uns-interchange-mvt.c: Same.

From-SVN: r226209