uboot-imx

test/py: Make print statements python 3.x safe

In python 3.x print must be called as a function rather than used as a
statement. Update uses of print to the function call syntax in order to
be python 3.x safe.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>