pppoe: T9395: apply the configuration being committed when a session returns

A PPPoE session is restarted from within the commit that changes it and comes
back up milliseconds later, while that commit is still running. The hook which
then configures the interface reads the running configuration, which until the
commit finishes is still the one from before it. Everything the commit adds is
missing at that point: for an interface newly set to IPv6 autoconf the hook
disabled router advertisements and autoconfiguration on the link, and nothing
turned them back on. The link kept its link-local address and never received a
global one, until the next commit or reconnect.

Which interface is hit varies with the order the commit happens to process
them, so this surfaced as an intermittent failure.

The hook now waits for the commit to finish before reading the configuration.

0 files changed, 0 insertions, 0 deletions