pgsql-server: Say "history is not supported" and remove "on this

Log Message:
-----------
Say "history is not supported" and remove "on this platform" for lack of
readline.

Modified Files:
--------------
pgsql-server/src/bin/psql:
input.c (r1.39 -> r1.40)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/bin/psql/input.c.diff?r1=1.39&r2=1.40)