remoteproc: introduce is_iomem to rproc_mem_entry

Introduce is_iomem to indicate this piece memory is iomem or not.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/1615029865-23312-4-git-send-email-peng.fan@oss.nxp.com


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