dmaengine: sh: setup_xref error handling

dmaengine: sh: setup_xref error handling

This patch modifies the type of setup_xref from void to int and handles
errors since the function can fail.

`setup_xref` now returns the (eventual) error from
`dmae_set_dmars`|`dmae_set_chcr`, while `shdma_tx_submit` handles the
result, removing the chunks from the queue and marking PM as idle in
case of an error.

Signed-off-by: Thomas Andreatta <thomas.andreatta2000@gmail.com>
Link: https://lore.kernel.org/r/20250827152442.90962-1-thomas.andreatta2000@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>