remoteproc: Properly deal with the resource table when detaching

If it is possible to detach the remote processor, keep an untouched
copy of the resource table.  That way we can start from the same
resource table without having to worry about original values or what
elements the startup code has changed when re-attaching to the remote
processor.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20210312162453.1234145-12-mathieu.poirier@linaro.org


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>