MLBEDSW-1998: Add support for new_axis_mask

-Added support for new_axis_mask
-Added support for more than 1 bit set in new/shrink_axis mask
-Added checks for strided slice in supported operator check
-Added assert if nothing has been put on NPU

Change-Id: I66e2d04784f14d7ad82371f5d649a455d576a818
Signed-off-by: Patrik Gustavsson <patrik.gustavsson@arm.com>