kselftest: alsa: Factor out check that values meet constraints

To simplify the code a bit and allow future reuse factor the checks that
values we read are valid out of test_ctl_get_value() into a separate
function which can be reused later. As part of this extend the test to
check all the values for the control, not just the first one.

Signed-off-by: Mark Brown <broonie@kernel.org>
1 file changed