spi: mxic: Fix an error handling path in mxic_spi_probe()

spi: mxic: Fix an error handling path in mxic_spi_probe()

If spi_register_master() fails, we must undo a previous
mxic_spi_mem_ecc_probe() call, as already done in the remove function.

Fixes: dac9b4d42c94 ("spi: mxic: Add support for pipelined ECC operations")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/09c81f751241f6ec0bac7a48d4ec814a742e0d17.1648980664.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>