Document bootxx_fat16 with a short description of why it differs from

bootxx_msdos.

usr.sbin/installboot/installboot.8

@@ -1,4 +1,4 @@
-.\"	$NetBSD: installboot.8,v 1.61 2006/12/23 19:50:20 wiz Exp $
+.\"	$NetBSD: installboot.8,v 1.62 2007/01/06 20:51:54 dsl Exp $
 .\"
 .\" Copyright (c) 2002-2003 The NetBSD Foundation, Inc.
 .\" All rights reserved.
@@ -34,7 +34,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd December 23, 2006
+.Dd January 6, 2007
 .Dt INSTALLBOOT 8
 .Os
 .Sh NAME
@@ -412,6 +412,20 @@ Primary bootstrap for file system type
 Installed into the bootstrap area of the file system by
 .Nm .
 .
+.It Pa /usr/mdec/bootxx_fat16
+Primary bootstrap for
+.Tn MS-DOS
+.Sy FAT16
+file systems.
+This differs from
+.Nm bootxx_msdos
+in that it doesn't require the filesystem to have been initialised with
+any
+.Ql reserved sectors .
+It also uses the information in the 
+.Ql Boot Parameter Block
+to get the media and filesytem properties.
+.
 .It Pa /usr/mdec/bootxx_ffsv1
 Primary bootstrap for
 .Sy FFSv1