Make Mux1H interface more generic

src/main/scala/ChiselUtil.scala

@@ -146,18 +146,18 @@ object UIntToOH
   */
 object Mux1H
 {
-  def apply[T <: Data](sel: Seq[Bool], in: Seq[T]): T = {
-    if (in.size == 1) in(0)
+  def apply[T <: Data](sel: Iterable[Bool], in: Iterable[T]): T = {
+    if (in.tail.isEmpty) in.head
     else {
       val masked = (sel, in).zipped map ((s, i) => Mux(s, i.toBits, Bits(0)))
-      in(0).fromBits(masked.reduceLeft(_|_))
+      in.head.fromBits(masked.reduceLeft(_|_))
     }
   }
-  def apply[T <: Data](in: Seq[(Bool, T)]): T = {
+  def apply[T <: Data](in: Iterable[(Bool, T)]): T = {
     val (sel, data) = in.unzip
     apply(sel, data)
   }
-  def apply[T <: Data](sel: Bits, in: Seq[T]): T =
+  def apply[T <: Data](sel: Bits, in: Iterable[T]): T =
     apply((0 until in.size).map(sel(_)), in)
 }