Pekka Paalanen authored Jun 13, 2022 and Pekka Paalanen committed Jun 16, 2022

These are the last places in weston-test-client-helper.c where using
image_header_from() will reduce the code line count and simplify the
code a little.

No change in behaviour.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>