Bump linux-source dependency to 6.7.9
cross-toolchain-base is unresolvable in OBS because nothing provides linux-source-6.6 >= 6.6.1. So, let's do the usual bump in this case.
cross-toolchain-base is unresolvable in OBS because nothing provides linux-source-6.6 >= 6.6.1. So, let's do the usual bump in this case.