ld: fix regressions with rett instructions in sparc tests.

ld: fix regressions with rett instructions in sparc tests.

A few tests in the ld testsuite were expecting the disassembler to
emit `rett' instructions in V9.  This patch updates the tests to
expect `return' instead.

ld/ChangeLog:

2017-04-24  Jose E. Marchesi  <jose.marchesi@oracle.com>

	* testsuite/ld-sparc/tlssunbin64.dd: Expect `return' instructions
	instead of `rett' in V9.
	* testsuite/ld-sparc/tlssunnopic64.dd: Likewise.
	* testsuite/ld-sparc/tlssunpic64.dd: Likewise.