Libraries/utils: remove bad link to MuxOH

This copies what is in master right now.

The presence of this link at an invalid URL is causing
  "make linkcheck" to fail.

http://spinalhdl.github.io/SpinalHDL/#spinal.lib.MuxOH$

source/SpinalHDL/Libraries/utils.rst

@@ -54,7 +54,7 @@ State less utilities
      - | Apply a mask on x to only keep the bit set from ``requests``.
        | it start looking in ``requests`` from the ``ohPriority`` position.
        | For example if ``requests`` is "1001" and ``ohPriority`` is "0010", the ``roundRobin`` function will start looking in `requests` from its second bit and will return "1000".
-   * - | `MuxOH <http://spinalhdl.github.io/SpinalHDL/#spinal.lib.MuxOH$>`_ (
+   * - | MuxOH (
        |   oneHot : IndexedSeq[Bool],
        |   inputs : Iterable[T]
        | )