Add note about CAM I/O scheduler.

UPDATING

@@ -31,6 +31,13 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 11.x IS SLOW:
 	disable the most expensive debugging functionality run
 	"ln -s 'abort:false,junk:false' /etc/malloc.conf".)
 
+20160414:
+	The CAM I/O scheduler has been committed to the kernel. There should
+	be no user visible impact. This does enable NCQ Trim on ada
+	SSDs. While the list of known rogues that claim support for
+	this but actually corrupt data is believed to be complete, be
+	on the lookout for data corruption.
+
 20160330:
 	The FAST_DEPEND build option has been removed and its functionality is
 	now the one true way.  The old mkdep(1) style of 'make depend' has