MLBEDSW-10905: Keep original shapes in FuseRescale

CopyInput/CopyOutput replaces the TensorConnection's shape with the
tensor's storage shape. This is undesired in case the original
network had a RESHAPE between our op and the RESCALE. In that case
we want to preserve the original shape.

Signed-off-by: Johan Gunnarsson <johan.gunnarsson@arm.com>
Change-Id: I1e78ce6ec03f71c06a35bb538d3388090178241c