remoteproc: Make function rproc_resource_cleanup() public

Make function rproc_resource_cleanup() public so that it can be
used by platform drivers when allocating resources to be used by
a detached remote processor.

Acked-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200714200445.1427257-8-mathieu.poirier@linaro.org


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