kern-tools: fix do_patch errors

kern-tools: fix do_patch errors

The linux-yocto repository and scripts can support a mode of
meta data management that merges a base meta branch to every
BSP branch. In this case, the scripts don't have to restore
a checkpoint for the meta data to be globally accessible.

The decision to restore or not is made based on whether or
not the meta branch is part of all branches or not.

The linux-yocto recipes have a sanity check to determine if
the requested SRCREV for meta data matches the head of the
meta branch (via do_validate_branches). If the wrong commit
is at the head, the meta branch is moved aside and the branch
reset to the right commit. This creates two meta branches that
contain the base meta data.

The test for integrated meta data mistakes this for a globally
merged set of meta data and doesn't restore the checkpoint, which
leads to build failures.

The immediate fix is to allow two branches to have the meta
data. The long term fix is to make the detection only consider
if the build branch contains the meta data.

(From OE-Core rev: bd794b92d12ceda2728520701e980b7a3cabd23d)

Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>