beam_except: Generalize translation to func_info instructions

The `beam_except` pass replaces some calls to `erlang:error/1` or
`erlang:error/2` with specialized instructions in order to reduce the
size of the BEAM code.

In functions that do binary matching, `beam_except` would fail to
translate the instructions that generate a `function_clause`
exception. Here is an example:

    bsum(<<H:16,T/binary>>, Acc) ->
        bsum(T, Acc+H);
    bsum(<<>>, Acc) ->
        Acc.

The BEAM code that generates the `function_clause` exception looks
like this:

    {label,4}.
      {test_heap,2,3}.
      {put_list,{x,1},nil,{x,1}}.

      %% The following two instructions prevents the translation.
      {bs_set_position,{x,2},{x,0}}.
      {bs_get_tail,{x,2},{x,0},3}.

      {test_heap,2,2}.
      {put_list,{x,0},{x,1},{x,1}}.
      {move,{atom,function_clause},{x,0}}.
      {line,...}.
      {call_ext,2,{extfunc,erlang,error,2}}.

Make the translation of `function_clause` exceptions smarter, so
that the following code will be produced:

    {label,4}.
      {bs_set_position,{x,2},{x,0}}.
      {bs_get_tail,{x,2},{x,0},3}.
      {jump,{f,1}}.                     %Jump to `func_info` instruction.

(This issue was noticed when looking at the code generated by
https://github.com/tomas-abrahamsson/gpb.)

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