Video, Storage and MCA changes/fixes.

1. Cirrus Logic GD54xx, Paradise/WD VGA now reset the interlace once a text mode is issued if not done automatically.
2. Paradise/WD's 15/16bpp modes using the 800x600 resolution now have the correct ma_latch, should fix most operating systems drivers using this combo.
3. More fixes (hopefully) to the accelerated pitch and rowoffset of the Trident TGUI cards (9440AGi and 96x0XGi), should fix issues with delayed displays mode changes under various operating systems (e.g.: Win3.1x).
4. Preliminary implementation of the Area Fill command of XGA, which is issued while using various painting and/or calc utilities on Win3.1x (IBM XGA updated drivers, e.g.: 2.12).
5. Preliminary (and incomplete) 4bpp XGA mode.
6. The XGA memory test for the 0xa5 using writes (used by various operating systems) no longer conflicts with DOS' XGAKIT's memory detection.
7. Small ROP fixes to both XGA and 8514/A.
8. Re-organized the mapping of the Mach32 chipset, especially when to enable the ATI mode or switching back to IBM mode, should fix LFB conflicts with various operating systems.
9. According to The OS/2 Museum, the Adaptec AHA-154xB series of SCSI cards fail the ASPI4DOS.SYS 3.36 signature check, so now make the changes accordingly.
10. Remove useless and crashy bios-less option of the Trantor T128.
11. The Image Manager 1024 card can also be used on a XT (although only if it has a V20/V30).
12. Re-organized the IBM PS/2 model 60 initialization as well as its right POS machine ID (though an update to sc.exe is still required for the POST memory amount to work normally).

src/include/86box/scsi_x54x.h

@@ -366,6 +366,7 @@ typedef struct SGE_t {
 #define X54X_INT_GEOM_WRITABLE 8
 #define X54X_MBX_24BIT         16
 #define X54X_ISAPNP            32
+#define X54X_HAS_SIGNATURE     64
 
 typedef struct x54x_t {
     /* 32 bytes */
@@ -404,7 +405,7 @@ typedef struct x54x_t {
 
     /* for multi-threading, keep these volatile */
     volatile uint8_t Status;
-    volatile uint8_t Interrupt; 
+    volatile uint8_t Interrupt;
     volatile uint8_t MailboxIsBIOS;
     volatile uint8_t ToRaise;
     volatile uint8_t flags;

src/include/86box/vid_xga.h

@@ -201,6 +201,8 @@ typedef struct xga_t {
         int dst_map;
         int bkgd_src;
         int fore_src;
+        int oldx;
+        int oldy;
         int x;
         int y;
         int sx;
@@ -211,6 +213,7 @@ typedef struct xga_t {
         int py;
         int pattern;
         int command_len;
+        int filling;
 
         uint32_t short_stroke;
         uint32_t color_cmp;