Change the batch_size to be power of two. Add param to the docstring

Signed-off-by: Manuel Saelices <msaelices@gmail.com>

mojo/stdlib/src/collections/inline_array.mojo

@@ -132,9 +132,12 @@ struct InlineArray[
 
     @always_inline
     @implicit
-    fn __init__[batch_size: Int = 100](out self, fill: Self.ElementType):
+    fn __init__[batch_size: Int = 64](out self, fill: Self.ElementType):
         """Constructs an empty array where each element is the supplied `fill`.
 
+        Parameters:
+            batch_size: The number of elements to unroll for filling the array.
+
         Args:
             fill: The element to fill each index.
         """