Bespoke trigger support was added when Linux v3.5 by this patch.

	commit 07bf84aa
	("ASoC: dpcm: Add bespoke trigger()")

test-component driver is using it, but this is because it indicates used
function for debug/trace purpose. Except test-component driver, bespoke
trigger has never been used over 10 years in upstream.

We can re-support it if needed in the future, but let's remove it for now,
because it just noise in upstream.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://patch.msgid.link/87v80ewmdi.wl-kuninori.morimoto.gx@renesas.comSigned-off-by: Mark Brown <broonie@kernel.org>