ASoC: soc-dapm: cleanup cppcheck warning at snd_soc_dapm_new_controls()

This patch cleanups below cppcheck warning.

sound/soc/soc-dapm.c:3786:30: style: The scope of the variable 'w' can be reduced. [variableScope]
 struct snd_soc_dapm_widget *w;
                             ^

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87k0l0u242.wl-kuninori.morimoto.gx@renesas.com


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