COMPMID-987: Make beta and gamma optional in BatchNormalization

Currently we have beta and gamma compulsory in Batch normalization. There are
network that might not need one or both of those. Thus these should be optional
with beta(offset) defaulting to zero and gamma(scale) to 1. Will also reduce
some memory requirements.

Change-Id: I15bf1ec14b814be2acebf1be1a4fba9c4fbd3190
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/123237
Tested-by: Jenkins <bsgcomp@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
20 files changed