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 <[e-mail]>
Acked-by: Kuninori Morimoto <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

Documentation/devicetree/bindings/sound/renesas,rsnd.txt

···
 	  - Register Description
 	   - CTUn Scale Value exx Register (CTUn_SVxxR)
 
-	${LINUX}/sound/soc/sh/rcar/ctu.c
+	${LINUX}/sound/soc/renesas/rcar/ctu.c
 	 - comment of header
 
 You need to use "simple-scu-audio-card" or "audio-graph-scu-card" for it.