remoteproc: k3: Refactor .stop rproc ops into common driver

remoteproc: k3: Refactor .stop rproc ops into common driver

The .stop rproc ops implementations in TI K3 DSP and M4 remoteproc
drivers put the remote processor into reset. Refactor the
implementations into ti_k3_common.c driver as k3_rproc_stop() and
register this common function as .stop ops in DSP and M4 drivers.

Signed-off-by: Beleswar Padhi <b-padhi@ti.com>
Tested-by: Judith Mendez <jm@ti.com>
Reviewed-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20250513054510.3439842-29-b-padhi@ti.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>