compilation fixes for OpenBSD

bochs/CHANGES

@@ -41,6 +41,7 @@ Bochs repository moved to the SVN version control !
 - VGA BIOS
 
 - SF patches applied
+  [3205979] Compilation fixes for OpenBSD by Brad Smith
   [3290979] acpi/muldiv64 endian bug by Heikki Lindholm
   [3289459] Mac OS X audio missing framework dependency by Heikki Lindholm
   [3267459] fix xrandr related crash by Heikki Lindholm

bochs/iodev/cdrom.cc

@@ -91,6 +91,9 @@ extern "C" {
 #include <sys/param.h>
 #include <sys/file.h>
 #include <sys/cdio.h>
+#if defined(__OpenBSD__)
+#include <sys/dkio.h>
+#endif
 #include <sys/ioctl.h>
 #include <sys/disklabel.h>
 // ntohl(x) et al have been moved out of sys/param.h in FreeBSD 5