[nvptx] Xfail sibcall execution tests
On nvptx I see the following FAIL:
...
FAIL: gcc.dg/sibcall-3.c execution test
...
The test-case states that "this test is xfailed on targets without sibcall
patterns".
The nvptx port doesn't have a sibcall pattern, so add an xfail. Likewise in
two similar test-cases.
Tested on nvptx.
gcc/testsuite/ChangeLog:
2022-02-20 Tom de Vries <tdevries@suse.de>
* gcc.dg/sibcall-10.c: Xfail execution test for nvptx.
* gcc.dg/sibcall-3.c: Same.
* gcc.dg/sibcall-4.c: Same.