refactor(bl): remove un-necessary variable

Remove un-necessary variable 'is_parent_image'
used in the 'load_auth_image_recursive' function.

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: Ie66f7e3cc82dd443da0b75d55adf3ae7e15b5f99
1 file changed