remoteproc: imx_rproc: Fix unreachable platform prepare_ops

Smatch reports unreachable code in imx_rproc_prepare(), where an early
return inside the reserved-memory parsing loop prevents platform
prepare_ops from being executed.

When of_reserved_mem_region_to_resource() fails, imx_rproc_prepare()
returns immediately, so the platform-specific prepare callback is never
called. As a result, prepare_ops such as imx_rproc_sm_lmm_prepare() on
i.MX95 have no chance to run.

This is problematic when Linux controls the M7 Logical Machine and is
responsible for preparing resources such as TCM. Without running the
platform prepare callback, loading the M7 ELF into TCM may fail if the
bootloader did not power up and initialize TCM.

Fix this by breaking out of the reserved-memory loop instead of
returning, allowing the platform prepare_ops to be executed as intended.

Fixes: edd2a99560 ("remoteproc: imx_rproc: Introduce prepare ops for imx_rproc_dcfg")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-remoteproc/aYYXAa2Fj36XG4yQ@p14s/T/#t
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
Link: https://lore.kernel.org/r/20260208-imx-rproc-fix-v1-1-ad74555eb9a4@nxp.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

drivers/remoteproc/imx_rproc.c

@@ -617,7 +617,7 @@ static int imx_rproc_prepare(struct rproc *rproc)
 
 		err = of_reserved_mem_region_to_resource(np, i++, &res);
 		if (err)
-			return 0;
+			break;
 
 		/*
 		 * Ignore the first memory region which will be used vdev buffer.