bootimg.bbclass:iso: use mkisofs -iso-level 3 for large iso
There will be problems when rootfs.img is larger than 4GB:
mkisofs: Value too large for defined data type. File /path/to/iso/rootfs.img is too large for current mkisofs settings - ignoring
And will get a wrong iso.
Check the size of ${ISODIR}/rootfs.img, use mkisofs -iso-level 3
when it exceeds 3.8GB, the specification is 4G - 1 bytes, we need
leave a few space for other files.
[YOCTO #6449]
Signed-off-by: Robert Yang <liezhi.yang@windriver.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
