soc: ti: wkup_m3_ipc: Use dev_err_probe

During probe the mailbox channel might not yet be available. Use
dev_err_probe to silence this deferred probe error message:
wkup_m3_ipc 44e11324.wkup_m3_ipc: IPC Request for A8->M3 Channel failed! -517

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20250509093652.1866566-1-alexander.stein@ew.tq-group.com


Signed-off-by: Nishanth Menon <nm@ti.com>