remoteproc: pru: Fix potential NULL pointer dereference in pru_rproc_set_ctable()

remoteproc: pru: Fix potential NULL pointer dereference in pru_rproc_set_ctable()

pru_rproc_set_ctable() accessed rproc->priv before the IS_ERR_OR_NULL
check, which could lead to a null pointer dereference. Move the pru
assignment, ensuring we never dereference a NULL rproc pointer.

Fixes: 102853400321 ("remoteproc: pru: Add pru_rproc_set_ctable() function")
Cc: stable@vger.kernel.org
Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
Link: https://lore.kernel.org/r/20250923112109.1165126-1-zhen.ni@easystack.cn
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>