macfb: don't clear interrupts when writing to DAFB_RESET

Traces from A/UX suggest that this register is only used to reset the framebuffer
LUT (colour lookup table) and not any other device state.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-ID: <20231026085650.917663-2-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

hw/display/macfb.c

@@ -585,8 +585,6 @@ static void macfb_ctrl_write(void *opaque,
         break;
     case DAFB_RESET:
         s->palette_current = 0;
-        s->regs[DAFB_INTR_STAT >> 2] &= ~DAFB_INTR_VBL;
-        macfb_update_irq(s);
         break;
     case DAFB_LUT:
         s->color_palette[s->palette_current] = val;