The RPF source memory pointers need to be offset to take the crop
rectangle into account. Offsets are computed in the RPF stream start,
which can happen (when using the DRM pipeline) after calling the RPF
.set_memory() operation that programs the buffer addresses.

The .set_memory() operation tries to guard against the problem by
skipping programming of the registers when the module isn't streaming.
This will however only protect the first use of an RPF in a DRM
pipeline, as in all subsequent uses the module streaming flag will be
set and the .set_memory() operation will use potentially incorrect
offsets.

Fix this by allowing the caller to decide whether to program the
hardware immediately or just cache the addresses. While at it refactor
the memory set code and create a new vsp1_rwpf_set_memory() that cache
addresses and calls the .set_memory() operation to apply them to the
hardware.

As a side effect the driver now writes all three DMA address registers
regardless of the number of planes, and initializes unused addresses to
zero.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>