spi: cadence: Fix spelling mistake "nunber" -> "number"

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

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Parshuram Thombare <pthombar@cadence.com>
Link: https://lore.kernel.org/r/20210928130712.990474-1-colin.king@canonical.com


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