bad include in inet_ntoa.c (versions openssh-3.7p1 & openssh-3.7.1p1)

[Spike Ilacqua]

"openbsd-compat/inet_ntoa.c" includes "inet_ntoa.h" which doesn't exist.
Deleting the "#include" line allows inet_ntoa.c to compile and the
resulting programs work fine.

->Spike