* check/ldstr-c.ok, check/ldstr-c.tst, check/ldstxi-c.ok,
check/ldstxi-c.tst, check/ldstxr-c.ok, check/ldstxr-c.tst:
New test case files testing load clobbering the base and/or
index register;
* check/ldst.inc: New file with common definition for all the
ldst* test cases.
check/Makefile.am, check/ldsti.tst, check/ldstr.tst,
check/ldstxi.tst, check/ldstxr.tst: Update for new common
definitions file and new register clobber ldst tests.
