Straighten ioctl.h

- include all ioctl subheaders, properly listing all letters;
- change FBD's ioctl calls to use 'B' instead of 'F', in
  preparation of the VND driver.

Change-Id: Ia718979568cc057f47cf505a89238d5b3b6695d4

include/sys/ioc_fbd.h

@@ -59,8 +59,8 @@ enum {
 };
 
 /* The I/O control requests. */
-#define FBDCADDRULE	_IOW('F', 1, struct fbd_rule)	/* add a rule */
-#define FBDCDELRULE	_IOW('F', 2, fbd_rulenum_t)	/* delete a rule */
-#define FBDCGETRULE	_IORW('F', 3, struct fbd_rule)	/* retrieve a rule */
+#define FBDCADDRULE	_IOW('B', 1, struct fbd_rule)	/* add a rule */
+#define FBDCDELRULE	_IOW('B', 2, fbd_rulenum_t)	/* delete a rule */
+#define FBDCGETRULE	_IORW('B', 3, struct fbd_rule)	/* retrieve a rule */
 
 #endif /* _S_I_FBD_H */