image: fix binary detection for small files
Previously, if the image file was less than 9 bytes long,
it was assumed to be an error when it could be a binary
image file. This patch makes OpenOCD detect these cases
as binary files.
Change-Id: I5b4dad2b547786246887812ac75907378fe58671
Signed-off-by: Marek Vrbka <marek.vrbka@codasip.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/7880
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>