spi: lpspi: Simplify some error message

dev_err_probe() already prints the error code in a human readable way, so
there is no need to duplicate it as a numerical value at the end of the
message.

Fixes: 12f62a85 ("spi: lpspi: Silence error message upon deferred probe")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-By: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://lore.kernel.org/r/253543c462b765eca40ba54c66f4e3fdf4acdeb7.1659735546.git.christophe.jaillet@wanadoo.fr


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