remoteproc/mediatek: skip if filesz is 0

The main purpose of the loop is to load the memory to the SCP SRAM.
If filesz is 0, can go to next program header directly.

We don't need to try to validate the FW binary for those filesz==0
segments.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Link: https://lore.kernel.org/r/20201116084413.3312631-3-tzungbi@google.com


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>