linux-yocto: update machines and default configuration
Fixes [YOCTO: #686]
During routine maintenance some base changes were re-wound on
the common branches. All machines still had these changes, but
any new machine branched from the common base would miss those
changes. This update restores those commits to the standard branch
and merges them out to all child branches.
The meta branch update adds a configuration item to support
live image booting on qemux86.
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
