.github: reorder CODEOWNERS owner entries
.github: reorder CODEOWNERS owner entries

I mis-interpreted the order of entries:
"Order is important; the last matching pattern takes the most precedence."
https://docs.github.com/en/github/creating-cloning-and-archiving-repositories/about-code-owners#codeowners-syntax

The idea is to not pull in all OS maintainers for vendor/ updates.

google/syzkaller,google/syzkaller,google/syzkaller,xairy/syzkaller,xairy/syzkaller,google/syzkaller,google/syzkaller,xairy/syzkaller,xairy/syzkaller,xairy/syzkaller,google/syzkaller,xairy/syzkaller,google/syzkaller,xairy/syzkaller