Fix clients getting 'Bad packet length' and 'Disconnecting: Packet corrupt'
when the NONECIPHER option is selected but not the HPN option. The server
banner was improperly sending a NULL byte after the newline causing confusion
on the client. This was an error in my own modifications to the HPN patch
in r383231.

This may have occurred with stale builds as well, such as running
'make configure' then 'portsnap update' and then 'make build'.

Pointyhat to: bdrewery
Reported by: many
PR: 199352