patman: Make print statements python 3.x safe

patman: Make print statements python 3.x safe

In python 3.x, print must be used as a function call. Convert all print
statements to the function call style, importing from __future__ where
we print with no trailing newline or print to a file object.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Simon Glass <sjg@chromium.org>