Bug 18923

	boot0cfg(8) currently has no way to select the default boot
	slice. Having such a mechanism is useful when boot0 is used
	with the `noupdate' option. Since turning on `noupdate'
	for the first time requires booting FreeBSD (which makes
	FreeBSD the default), there is no direct way to make some
	non-FreeBSD partition the permanent default.

	[Indirect ways to achieve this which do work include booting
	FreeBSD from a floppy or CDROM (so as not to disturb the current
	default slice) and then running boot0cfg, or manually editing
	the byte at offset 0x1b9 in the MBR.]

	The patch included below adds a new `-s' option to boot0cfg
	that allows the default boot slice to be configured.

Fix: Apply the following patch in src/usr.sbin/boot0cfg.
How-To-Repeat: 
	- Take a disk with two slices:

		F1 Dos
		F2 FreeBSD

	- Attempt to make "F1 Dos" the permanent default, so it will
	always be the default regardless of the last selection made.

	- Discover that in order to run "boot0cfg -o noupdate", one must
	first boot FreeBSD. Running "boot0cfg -o noupdate" then makes
	"F2 FreeBSD" the permanent default.