This reverts commit b25920dfc07452833895ad00b42db7e581b3cec8.
The `log.Printf` messages are causing panics in corp, in particular:
> panic: please use tailscale.com/logger.Logf instead of the log package
Fixing the TKA code to plumb through a logger properly is going to be
a hassle, so for now remove these logs to unblock merges to corp.
Updates tailscale/corp#39455
Signed-off-by: Alex Chan <alexc@tailscale.com>