Current logic only support main processor to stop/start the remote
processor after crash. However to SoC, such as i.MX8QM/QXP, the
remote processor could do attach recovery after crash and trigger watchdog
to reboot itself. It does not need main processor to load image, or
stop/start remote processor.

Introduce two functions: rproc_attach_recovery, rproc_boot_recovery
for the two cases. Boot recovery is as before, let main processor to
help recovery, while attach recovery is to recover itself without help.
To attach recovery, we only do detach and attach.
Acked-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20220928064756.4059662-3-peng.fan@oss.nxp.comSigned-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>