intel-ci: Ignore performance-only pread/pwrite "tests"

We don't need to waste time running perf-only test cases when we are not
manually checking results. ezbench is that away!

References: https://bugs.freedesktop.org/show_bug.cgi?id=109640


Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Petri Latvala <petri.latvala@intel.com>