Re: execute pkg_postinst_ontarget when read-only-rootfs-delayed-postinsts is set for a read only rootfs

Hi Alex,

> 
> I would only suggest to grep the poky tree for
> read-only-rootfs-delayed-postinsts to see how it's implemented
> 

already did before my first post. Basically, the only place in all of poky where this feature is used is in rootfs.py to turn off a bb.fatal when you have a delayed postinstall script and a read-only rootfs. This is also what the doc says

> 
> read-only-rootfs-delayed-postinsts: when specified in conjunction with read-only-rootfs
> , specifies that post-install scripts are still permitted (this assumes
> that the root filesystem will be made writeable for the first boot; *this
> feature does not do anything to ensure that - it just disables the check
> for post-install scripts* )

The _uninstall_unneeded method in rootfs.py removes packages with postinstall steps if read-only-rootfs is set. However, as I suggested in my patch, the check should also take into account the read-only-rootfs-delayed-postinsts feature, which allows postinstall code even for read-only rootfs.