Added preliminary Adaptec 154x emulation, needs fixing in the Read 10 command.

Made ATAPI derived from SCSI.
Added proper S/G emulation for SCSI DMA.
Added SCSI CD-ROM emulation, preserving all the former ATAPI commands as well.

src/cdrom-ioctl.h

@@ -7,6 +7,8 @@
 /* this header file lists the functions provided by
    various platform specific cdrom-ioctl files */
 
+extern uint32_t cdrom_capacity;
+   
 extern int ioctl_open(char d);
 extern void ioctl_reset();