Make sure OLD_CURSOR code is only for SUNDISPLAY. (#279)

This is work in progress on Interlisp/medley#84.

bin/compile-flags

@@ -97,7 +97,8 @@ ORG_FILPCORSORBAR If true, you get the pixwin version of cursor changing;
 		otherwise, it gets done by direct writes into the display
 		region.
 OLD_CURSOR	If true, uses the pixwin cursor code (e.g., win_setcursor);
-		otherwise, uses the direct-write technique.
+		otherwise, uses the direct-write technique. This is only needed
+		for SUNDISPLAY.
 OS4_TYPE4BUG	If true, includes the patches around SunOS 4.0.x's failure
 		to tell you you've got a Type-4 keyboard.
 ALLDIRSEARCH	CURRENTLY HARD DISABLED IN directory.c; looks like it 

inc/bitblt.h

@@ -57,7 +57,7 @@ extern int DisplayRasterWidth;
 #define ShowCursor { (currentdsp->mouse_visible)(IOPage68K->dlmousex, \
 												  IOPage68K->dlmousey); }
 
-#elif OLD_CURSOR
+#elif defined(SUNDISPLAY) && defined(OLD_CURSOR)
 extern struct winlock DisplayLockArea;
 #define	HideCursor	\
 	ioctl( LispWindowFd, WINLOCKSCREEN, &DisplayLockArea)

src/dspsubrs.c

@@ -99,7 +99,7 @@ void DSP_Cursor(LispPTR *args, int argnum)
   extern int ScreenLocked;
   extern DLword *EmCursorX68K, *EmCursorY68K;
   extern int LastCursorX, LastCursorY;
-#if !defined(OLD_CURSOR)
+#if defined(SUNDISPLAY) && !defined(OLD_CURSOR)
   static int Init = T;
 #endif
 

src/keyevent.c

@@ -173,6 +173,8 @@ typedef struct {
 
 /*  EmXXXX68K are already swapped, no need for GETWORD */
 
+
+#ifdef SUNDISPLAY
 #ifdef OLD_CURSOR
 #define TrackCursor(cx, cy)                          \
   {                                                  \
@@ -190,6 +192,7 @@ typedef struct {
     *EmCursorY68K = cy;                              \
   }
 #endif /* OLD_CURSOR */
+#endif /* SUNDISPLAY */
 
 /* commented out is some code that would also clobber
         Irq_Stk_Check & Irq_Stk_End to force