Oops, in the maxpartitions=52 case, the correct multiplier is 64

Noticed by krw and myself at the same time

etc/MAKEDEV.mi

@@ -1,7 +1,7 @@
 define(COMM,`#')dnl
 include(MAKEDEV.sub)dnl
 dnl
-vers(a, {-$OpenBSD: MAKEDEV.mi,v 1.86 2025/10/15 00:24:40 deraadt Exp $-})dnl
+vers(a, {-$OpenBSD: MAKEDEV.mi,v 1.87 2025/10/15 17:53:23 deraadt Exp $-})dnl
 dnl
 divert(1)dnl
 {-#-}
@@ -66,7 +66,8 @@ show_vers()dnl <-- now that all files are included, show versions
 dnl
 divert(2)dnl
 PATH=/sbin:/usr/sbin:/bin:/usr/bin
-MAXPARTITIONS=`sysctl -n kern.maxpartitions`
+UNITMULT=`sysctl -n kern.maxpartitions`
+[ $UNITMULT == 52 ] && UNITMULT=64
 T=$0
 
 # set this to echo for Echo-Only debugging
@@ -137,9 +138,9 @@ dnl
 dodisk()
 {
 	[ "$DEBUG" ] && set -x
-	n=Add(Mult(${5}, ${7:-$MAXPARTITIONS}), ${6}) count=0
+	n=Add(Mult(${5}, ${7:-$UNITMULT}), ${6}) count=0
 	_extra=
-	[ $MAXPARTITIONS == 64 ] && _extra="q r s t u v w x y z \
+	[ $UNITMULT == 64 ] && _extra="q r s t u v w x y z \
 	    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z"
 	for d in a b c d e f g h i j k l m n o p $_extra
 	do
@@ -157,12 +158,12 @@ dnl 3. blkmaj  - block device major number
 dnl 4. chrmaj  - character device major number
 dnl 5. unit    - beginning unit number for character devices
 dnl 6. off     - offset from 0 for all minor numbers
-dnl 7. step    - optional, defaults to $MAXPARTITIONS, creating 16 or 52 nodes per device
+dnl 7. step    - optional, defaults to $UNITMULT, creating 16 or 52 nodes per device
 dnl
 
 dodisk2()
 {
-	n=Add(Mult({-$-}5, ${7:-$MAXPARTITIONS}), {-$-}6)
+	n=Add(Mult({-$-}5, ${7:-$UNITMULT}), {-$-}6)
 	M {-$-}1{-$-}2a b {-$-}3 $n 640 operator
 	M r{-$-}1{-$-}2a c {-$-}4 $n 640 operator
 	n=Add($n, 2)