fix(z): runtime error: index out of range for !amd64 env #287

fix `runtime error: index out of range`  in non-amd64 (arm64) env

(cherry picked from commit efb105d)

z/simd/search.go

@@ -20,7 +20,7 @@ package simd
 
 // Search uses the Clever search to find the correct key.
 func Search(xs []uint64, k uint64) int16 {
-	if len(xs) < 8 {
+	if len(xs) < 8 || (len(xs) % 8 != 0) {
 		return Naive(xs, k)
 	}
 	var twos, pk [4]uint64