Now this is the behaviour for the choice:
if you select P2P, it's built and selected. Default is E2E_ONLY.
The P2P is built by default configuration, and the mechanism
is selected at configuration time. Default is E2E. If you
choose E2E_ONLY and configure pdelay, it will ignore the config.
(Suboptimal but I'm lazy: do *not* use E2E_ONLY for those archs.
The default is e2e until changed at run time.
Signed-off-by: Alessandro Rubini <email@example.com>