PRINT calls FLATSIZE too often

[jonl,psz at MIT-MC]

At PRINLP, there is the test of the "TERPRI" condition, and
if it isn't being used, there is no need to have called FLATSIZE.
We should have each call to PRINLP do this test first before
computating the flatsize - it makes a big difference in the use
of USER-HUNKS, since the flatsize computation time may be
quite large.