grow arm64 ramdisk

src/etc/etc.arm64/disktab

@@ -1,10 +1,10 @@
-# $OpenBSD: disktab,v 1.1 2017/01/11 17:05:29 patrick Exp $
+# $OpenBSD: disktab,v 1.2 2018/09/18 13:45:09 deraadt Exp $
 
 # Leave nc=16; adjust size using: ns
 rdroot|ramdiskroot|RAM-disk root FS image:\
-	:dt=rdroot:se#512:nc#16:nt#2:ns#480:\
-	:ta=4.2BSD:oa#0:pa#15360:fa#512:ba#4096:\
-	:ob#0:pb#0:oc#0:pc#15360:
+	:dt=rdroot:se#512:nc#16:nt#2:ns#512:\
+	:ta=4.2BSD:oa#0:pa#16384:fa#512:ba#4096:\
+	:ob#0:pb#0:oc#0:pc#16384:
 
 miniroot:\
 	:dt=rdroot:se#512:nc#9:nt#16:ns#256:\