Changes to 8514/A compatible stuff (November 2nd, 2024)

1. vga_on global variable removed, as it didn't play well with 2 subsystems at once (8514/A and XGA both enabled).
2. Emulate the Foreground/Background Color aliases of PIX_TRANS properly when not executing a command.
3. Voodoo 3D override now works properly (again) with Mach32 PCI cards and others by turning the 8514/A timer off and on accordingly.

src/include/86box/vid_8514a.h

@@ -42,7 +42,6 @@ typedef union {
 typedef struct ibm8514_t {
     rom_t bios_rom;
     rom_t bios_rom2;
-    rom_t bios_rom3;
     hwcursor8514_t hwcursor;
     hwcursor8514_t hwcursor_latch;
     uint8_t        pos_regs[8];
@@ -228,6 +227,7 @@ typedef struct ibm8514_t {
     uint32_t vram_amount;
     int      vram_512k_8514;
     PALETTE  _8514pal;
+    int      vendor_mode;
 
     latch8514_t latch;
 } ibm8514_t;

src/include/86box/vid_svga.h

@@ -79,6 +79,7 @@ typedef struct svga_t {
     uint8_t fcr;
     uint8_t hblank_overscan;
     uint8_t vidsys_ena;
+    uint8_t sleep;
 
     int dac_addr;
     int dac_pos;
@@ -297,8 +298,6 @@ typedef struct svga_t {
     void *  xga;
 } svga_t;
 
-extern int      vga_on;
-
 extern void     ibm8514_poll(void *priv);
 extern void     ibm8514_recalctimings(svga_t *svga);
 extern uint8_t  ibm8514_ramdac_in(uint16_t port, void *priv);
@@ -314,6 +313,8 @@ extern void     ibm8514_short_stroke_start(int count, int cpu_input, uint32_t mi
 extern void     ibm8514_accel_start(int count, int cpu_input, uint32_t mix_dat, uint32_t cpu_dat, svga_t *svga, int len);
 
 #ifdef ATI_8514_ULTRA
+extern void     ati8514_out(uint16_t addr, uint8_t val, void *priv);
+extern uint8_t  ati8514_in(uint16_t addr, void *priv);
 extern void     ati8514_recalctimings(svga_t *svga);
 extern uint8_t  ati8514_mca_read(int port, void *priv);
 extern void     ati8514_mca_write(int port, uint8_t val, void *priv);