ASoC: renesas, rsnd: Update file path

The "sound/soc/sh" directory has been renamed to "sound/soc/renesas".
Update the reference in renesas,rsnd.txt to reflect the new file path
for consistency.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://patch.msgid.link/20241025150511.722040-3-prabhakar.mahadev-lad.rj@bp.renesas.com


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