spi: s3c64xx: Fix spelling mistake "hannel" -> "channel"

There is a spelling mistake in a dev_err message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Link: https://lore.kernel.org/r/20220608081912.2083086-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>