perf test cs-etm: Speed up basic test

perf test cs-etm: Speed up basic test

Like the name says, this should be the most basic test possible. Kernel
recording is slow and already has coverage on the systemwide test. Perf
report output also has coverage elsewhere. 'ls' also produces more trace
than 'true'.

We only want to test if the combination of recording options works at
all, so fix all of these things to make it as fast as possible.

Reviewed-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Cc: Amir Ayupov <aaupov@meta.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paschalis Mpeis <Paschalis.Mpeis@arm.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>