remoteproc: k3-r5: Jump to error handling labels in start/stop errors

In case of errors during core start operation from sysfs, the driver
directly returns with the -EPERM error code. Fix this to ensure that
mailbox channels are freed on error before returning by jumping to the
'put_mbox' error handling label. Similarly, jump to the 'out' error
handling label to return with required -EPERM error code during the
core stop operation from sysfs.

Fixes: 3c8a9066

 ("remoteproc: k3-r5: Do not allow core1 to power up before core0 via sysfs")
Signed-off-by: Beleswar Padhi <b-padhi@ti.com>
Link: https://lore.kernel.org/r/20240506141849.1735679-1-b-padhi@ti.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>