When authorized_file doesn't contain new-line character at the end,
configure_ironic_ssh_keypair() just append new key to the existed line,
as result both keys becomes corrupted. The patch adds a check for
last character in the authorized_key file, if new-line is missed
add it.
Change-Id: I64a7bba5f3c7dee76ae2faf659af1231280f2b8b
Closes-Bug: #1611207
600e2e4057