MLBEDSW-4803: Output diff fix for MobileNetV3

This commit moves a piece of code back into a loop
but with a flag to make sure that the code is only
executed once per loop rather than potentially every
iteration. This solves the issue of an output diff
because of LUT DMAs occurring before weight DMAs.

Signed-off-by: Dwight Lidman <dwight.lidman@arm.com>
Change-Id: I3e597f0a955154af3d87febacea1b3920d53b7c2