Fix geometry of rdroot entry so

nt# * ns# * nc# == pc# == pa#
which makes for a better disklabel via getdiskbyname().
ok deraadt@

src/etc/etc.i386/disktab

@@ -1,4 +1,4 @@
-#	$OpenBSD: disktab,v 1.22 2014/03/02 15:42:49 deraadt Exp $
+#	$OpenBSD: disktab,v 1.23 2015/07/27 19:17:10 krw Exp $
 
 mini34|gzip bsd.rd disk image 3.40625MB:\
 	:ty=SCSI:se#512:nt#1:ns#64:nc#109:\
@@ -29,7 +29,7 @@ floppy5|5in|5.25in High Density Floppy:\
 	:pc#2400:oc#0:bc#4096:fc#512:
 
 rdroot|ramdiskroot|RAM-disk root FS image:\
-	:ty=ramdisk:se#512:nt#2:ns#128:nc#16:\
+	:ty=ramdisk:se#512:nt#2:ns#121:nc#16:\
 	:pa#3872:oa#0:ta=4.2BSD:ba#4096:fa#512:\
 	:pb#0:ob#0:tb=swap:\
 	:pc#3872:oc#0: