The variant is required for platform match while pulling images
for ARM platforms. Currently, the cpuVariant only would be assigned
on linux/arm|arm64 platforms. Other platforms this variable would
be empty. So we can use this cpuVariant to initialize the Variant
field.
Change-Id: Ic065be9b502f1e662445daa61a0973bf56385b37
Signed-off-by: Wei Chen <Wei.Chen@arm.com>
Signed-off-by: Penny Zheng <Penny.Zheng@arm.com>