Patch to src/nrelease/root/README

[Tim Wickberg <me@xxxxxxxxxxx>]

Adds a section mentioning how to use MAKEDEV to add device nodes for 
filesystems when you're not using the first slice on the disk.

Thanks to the people in #dragonflybsd.

-- Tim Wickberg
   me@xxxxxxxxxxx

80,85d79
< 	# Create the device nodes for the filesystems. Do this only if you
< 	# are not using the ad0s1 slice. Change the slice number to match the  
< 	# slice you are using.
< 	#	
< 	cd /dev && MAKEDEV ad0s2a
<