drivers: of: add automated assignment of reserved regions to client devices

This patch adds code for automated assignment of reserved memory regions
to struct device. reserved_mem->ops->device_init()/device_cleanup()
callbacks are called to perform reserved memory driver specific
initialization and cleanup

Based on previous code provided by Josh Cartwright <joshc@codeaurora.org>

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>

diff --cc drivers/of/of_reserved_mem.c
Simple merge

diff --cc include/linux/of_reserved_mem.h
Simple merge