on reviewing runedecompose, the idea that one could put a non-bmp
rune in the even half of the __decompose2 table if it decomposed to
two bmp runes requires pre-knowledge of this fact when searching.

so remove that possiblity from the code.

Reference: /n/atom/patch/applied2013/runedctidy
Date: Mon Jun 24 17:19:02 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/libc/port/runedecompose.c	Mon Jun 24 17:14:57 2013
+++ /sys/src/libc/port/runedecompose.c	Mon Jun 24 17:14:57 2013
@@ -56,11 +56,13 @@
 			return 0;
 		}
 	}
-	q = bsearch64(a, __decompose264, nelem(__decompose264)/2, 2);
-	if(q){
-		d[0] = q[1] >> 32;
-		d[1] = q[1] & 0xfffffff;
-		return 0;
+	else{
+		q = bsearch64(a, __decompose264, nelem(__decompose264)/2, 2);
+		if(q){
+			d[0] = q[1] >> 32;
+			d[1] = q[1] & 0xfffffff;
+			return 0;
+		}
 	}
 	return -1;
 }