ASoC: fsl: mpc5200_dma: Convert to devm_ioremap()

ASoC: fsl: mpc5200_dma: Convert to devm_ioremap()

Replace ioremap() with devm_ioremap() so the mapping is released
automatically when the device is unbound. Remove the corresponding
iounmap() calls from the error path in mpc5200_audio_dma_create() and
from mpc5200_audio_dma_destroy().

Since devm_ioremap() failure already returns directly and no other
cleanup is needed at that point, simplify the kzalloc error path to
return -ENOMEM directly instead of jumping to the now-removed out_unmap
label.

Signed-off-by: Jihed Chaibi <jihed.chaibi.dev@gmail.com>
Link: https://patch.msgid.link/20260324224530.102164-1-jihed.chaibi.dev@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>