ASoC: rsnd: Fix RSND_SOC_MASK width to single nibble

ASoC: rsnd: Fix RSND_SOC_MASK width to single nibble

RSND_SOC_MASK was defined as (0xFF << 4), spanning bits 4-11. This is
wider than needed since only nibble B (bits 7:4) is used for SoC
identifiers. Narrow it to (0xF << 4) to match the intended single-nibble
allocation and prevent overlap with bits 8-11 which will be used by
upcoming RZ series flags.

No functional change, since the only current user (RSND_SOC_E) fits
within a single nibble.

Fixes: ba164a49f8f7 ("ASoC: rsnd: src: Avoid a potential deadlock")
Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://patch.msgid.link/20260525110230.4014435-3-john.madieu.xa@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>