custompline(SUPPRESS_HISTORY,...) for curses

The curses interface already has a hack to keep 'Count: 12', 'Count:
123' intermediate multi-digit counts out of its message recall history
for ^P, but it was flushing real messages when getpos()'s 'autodescribe'
reported what the cursor moved over.  Overload the count hack to support
 putstr(WIN_MESSAGE, ATR_NOHISTORY, text)
(which is what custompline(SUPPRESS_HISTORY, ...) eventually calls).

The conditional logic for when to create the 'count_window' was pretty
convoluted.  This simplification has the same semantics but I don't
have PDCURSES to actually verify that.

doc/fixes36.2

@@ -1,4 +1,4 @@
-$NHDT-Branch: NetHack-3.6.2-beta01 $:$NHDT-Revision: 1.249 $ $NHDT-Date: 1549334449 2019/02/05 02:40:49 $
+$NHDT-Branch: NetHack-3.6.2-beta01 $:$NHDT-Revision: 1.250 $ $NHDT-Date: 1549584261 2019/02/08 00:04:21 $
 
 This fixes36.2 file is here to capture information about updates in the 3.6.x
 lineage following the release of 3.6.1 in April 2018. Please note, however,
@@ -437,6 +437,8 @@ tty: fix leftover display artifact when the last field on the row got placed
 X11: its use of genl_status_update exposed a negative index use that could
 	lead to a segfault
 X11: rollback disabling of keystroke input for PICK_NONE menus (for scrolling)
+curses: catch up with tty to not put dolook/whatis autodescribe feedback into
+	^P message recall (multi-digit count feedback was already handled)
 
 
 Platform- and/or Interface-Specific Fixes or Features