libdraw: allow 32-bit Runes

R=, rsc
CC=
http://codereview.appspot.com/196054
diff --git a/src/libdraw/buildfont.c b/src/libdraw/buildfont.c
index fa50b6e..75b59b1 100644
--- a/src/libdraw/buildfont.c
+++ b/src/libdraw/buildfont.c
@@ -70,7 +70,7 @@
 		}
 		max = strtol(s, &s, 0);
 		s = skip(s);
-		if(*s==0 || min>=65536 || max>=65536 || min>max){
+		if(*s==0 || min>Runemax || max>Runemax || min>max){
 			werrstr("illegal subfont range");
     Err3:
 			freefont(fnt);