firmware: cs_dsp: tests: Depend on FW_CS_DSP rather then enabling it

firmware: cs_dsp: tests: Depend on FW_CS_DSP rather then enabling it

FW_CS_DSP gets enabled if KUNIT is enabled. The test should rather
depend on if the feature is enabled. Fix this by moving FW_CS_DSP to the
depends on clause.

Fixes: dd0b6b1f29b9 ("firmware: cs_dsp: Add KUnit testing of bin file download")
Signed-off-by: Nico Pache <npache@redhat.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://patch.msgid.link/20250411123608.1676462-4-rf@opensource.cirrus.com
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>