grow sparc64 miniroot a little

src/etc/etc.sparc64/disktab

@@ -1,4 +1,4 @@
-# $OpenBSD: disktab,v 1.17 2015/08/14 23:45:56 krw Exp $
+# $OpenBSD: disktab,v 1.18 2019/06/08 15:49:22 deraadt Exp $
 
 miniroot:\
 	:dt=rdroot:se#512:nt#2:ns#64:nc#90:\
@@ -27,7 +27,7 @@ fakecdrom|Fake image for Bootable CDROM:\
 	:pd#1310720:od#0:bd#8192:fd#1024:td=4.2BSD:
 
 fakeramdisk:\
-	:dt=rdroot:se#512:nt#1:ns#32:nc#180:\
-	:pa#5760:oa#0:ba#8192:fa#4096:ta=4.2BSD:\
-	:pc#5760:oc#0:
+	:dt=rdroot:se#512:nt#1:ns#32:nc#190:\
+	:pa#6080:oa#0:ba#8192:fa#4096:ta=4.2BSD:\
+	:pc#6080:oc#0: