mkpkg_binary-addons: don't checkout and create a new branch at the sa…

[lrusak]

…me time

You can't checkout a branch and create a new branch at the same time. This only worked for git hashes.

So in the past you would be left with adsp.basic-.tar.xz

$ git checkout v0.2.0 -b ref-v0.2.0
fatal: Cannot update paths and switch to branch 'ref-v0.2.0' at the same time.
Did you intend to checkout 'v0.2.0' which can not be resolved as commit?

Separating the checkout into two lines fixes this issue.

Since kodi tells us either a git hash or a branch, this method works fine and is needed for when the branch jarvis addons anyways (which has already happened).