ASoC: wm5100: fix spelling mistake: "micropone" -> "microphone"

Trivial fix to spelling mistake in dev_err message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>