Fix non working demos using AddInterServer through Disable and removal of uncessary delay in Enable.s (#150)

Co-authored-by: Kamelito <kamelitoloveless@gmail.com>

Author: Kamelitoloveless

arch/m68k-amiga/exec/enable.S

@@ -1,5 +1,5 @@
 /*
-    Copyright © 1995-2010, The AROS Development Team. All rights reserved.
+    Copyright � 1995-2010, The AROS Development Team. All rights reserved.
     $Id$
 
     Desc: Enable() - Allow interrupts to occur after Disable().
@@ -72,6 +72,4 @@ AROS_SLIB_ENTRY(Enable,Exec,21):
 	subq.b	#1,%a6@(IDNestCnt)
 	bge.s	0f
 	move.w	#0xc000,0xdff09a
-        tst.b 0xbfe001
-	tst.b 0xbfe001
 0:	rts

arch/m68k-amiga/timer/lowlevel.c

@@ -1,5 +1,5 @@
 /*
-    Copyright © 1995-2018, The AROS Development Team. All rights reserved.
+    Copyright � 1995-2018, The AROS Development Team. All rights reserved.
     $Id$
 
     Desc: CIA timer.device
@@ -264,7 +264,10 @@ AROS_INTH1(cia_vbint, struct TimerBase *, TimerBase)
 		return 0;
 	inc64(&TimerBase->tb_vb_count);
 
-	Disable();
+	/* Disable(); */
+	asm volatile ("move.w #0x4000,0xdff09a\n");
+	/* Disable() / Enable() here interfere with demos using AddInterServer called from Disable() */
+	/* replaced by disabling / enabling Interrupt using INTENA */
     	ForeachNodeSafe(&TimerBase->tb_Lists[UNIT_VBLANK], tr, next) {
 	    	if (cmp64(&TimerBase->tb_vb_count, &tr->tr_time)) {
 	           	Remove((struct Node *)tr);
@@ -280,7 +283,8 @@ AROS_INTH1(cia_vbint, struct TimerBase *, TimerBase)
 	if (IsListEmpty(&TimerBase->tb_Lists[UNIT_VBLANK])) {
 		TimerBase->tb_vblank_on = FALSE;
 	}
-	Enable();
+	/* Enable(); */
+	asm volatile ("move.w #0xc000,0xdff09a\n");
 
 	return 0;