chore: use tabs for indentation

This patch changes the definition of image_info_t to follow the TF-A
coding style documented at
https://trustedfirmware-a.readthedocs.io/en/latest/process/coding-style.html

Signed-off-by: Jorge Troncoso <jatron@google.com>
Change-Id: I17af22b4ba60b41cf0b5fa84ac47beeb1536edcc
1 file changed