Make 'image_offset' unsigned

Since 'image_offset' represents a file offset, it is always unsigned. Make
its type unsigned to prevent that a cast has to be introduced in the next
patch when assigning an image offset to the 'lo_offset' member.

Bug: 194450129
Test: Built Android images and installed these on an Android phone.
Change-Id: I884d91647669560148c5f62cef68633b1a8c7a7d
Signed-off-by: Bart Van Assche <bvanassche@google.com>
5 files changed