[Bug other/92870] new test case gcc.dg/vect/vect-shift-5.c fails starting with its introduction in r279114

[sudi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92870

--- Comment #1 from sudi at gcc dot gnu.org ---
Ah I think I need a better effective target check. This test would only pass
for target that have a vector/scalar shift/rotate optab.