spi: spi-imx: Use dev_err_probe for failed DMA channel requests

If dma_request_chan() fails, no error is shown nor any information is
shown in /sys/kernel/debug/devices_deferred if -EPROBE_DEFER is returned.
Use dev_err_probe to fix both problems.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Link: https://msgid.link/r/20240110085403.457089-1-alexander.stein@ew.tq-group.com
Signed-off-by: Mark Brown <broonie@kernel.org>