Added the CMD640 (but the associated PB520R is not yet properly done, needs the 82091AA, so it's disabled until I implement it), fixed initialization of the IDE registers on the SMSC southbridge, bumped up the number of emulated serial ports to 4 (was 2), and added the ability to properly have multiple W83977's on a single machine.

src/include/86box/serial.h

@@ -32,6 +32,10 @@
 #define SERIAL1_IRQ		4
 #define SERIAL2_ADDR		0x02f8
 #define SERIAL2_IRQ		3
+#define SERIAL3_ADDR		0x03e8
+#define SERIAL3_IRQ		4
+#define SERIAL4_ADDR		0x02e8
+#define SERIAL4_IRQ		3
 
 
 struct serial_device_s;