remoteproc: k3-r5: Do not allow core1 to power up before core0 via sysfs

PSC controller has a limitation that it can only power-up the second
core when the first core is in ON state. Power-state for core0 should be
equal to or higher than core1.

Therefore, prevent core1 from powering up before core0 during the start
process from sysfs. Similarly, prevent core0 from shutting down before
core1 has been shut down from sysfs.

Fixes: 6dedbd1d

 ("remoteproc: k3-r5: Add a remoteproc driver for R5F subsystem")
Signed-off-by: Beleswar Padhi <b-padhi@ti.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240430105307.1190615-3-b-padhi@ti.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>