spi: microchip-core: switch to use devm_spi_alloc_master()

Switch to use devm_spi_alloc_master() to simpify error path.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220713025657.3524506-3-yangyingliang@huawei.com


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