Split bootsector execution code out into bootsector.c.

Added basic El Torito ISO image boot capability

src/arch/i386/include/bootsector.h

@@ -0,0 +1,12 @@
+#ifndef _BOOTSECTOR_H
+#define _BOOTSECTOR_H
+
+/** @file
+ *
+ * x86 bootsector image format
+ */
+
+extern int call_bootsector ( unsigned int segment, unsigned int offset,
+			     unsigned int drive );
+
+#endif /* _BOOTSECTOR_H */

src/arch/i386/include/int13.h

@@ -37,6 +37,8 @@ struct block_device;
 #define INT13_EXTENDED_WRITE		0x43
 /** Get extended drive parameters */
 #define INT13_GET_EXTENDED_PARAMETERS	0x48
+/** Get CD-ROM status / terminate emulation */
+#define INT13_CDROM_STATUS_TERMINATE	0x4b
 
 /** @} */