kern-tools: fix non-inheriting branch names

kern-tools: fix non-inheriting branch names

Importing the following tools SRCREV:

    kgit-meta: exclude explicit branches from name calculations

    kernel branches are constructed during patching of the tree by
    constructing a '/' based hierarchy of names as each branch
    directive is encountered.

    But if a "branch $name $branchpoint" is used, the entire branch
    name is supplied so no additions to the hierarchy should
    happen. As such, that type of branch command should not be part
    of branch name calculation and preparation.

(From OE-Core rev: a3884938233c8a2d6861b1d4e6be5b9824d3b131)

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