MLBEDSW-10781: Fix transpose with LUT assert

Ethos-U55 transpose with LUT generates an assert as a result
of default-initialised values in the block config.
This commit moves the LUT insertion until after a suitable
block config is available.

Signed-off-by: Philip Hall <philip.hall@arm.com>
Change-Id: If2137253696d26f996605ec9bf2fab1a1c69c229