bug#15848: 24.3.50; cperl-mode + which-function: Improve reporting (corner case)

[Jambunathan K]

Your patch looks good.  Thanks.

Before trying the patch, I had the "wrong" impression that headN lines
won't be displayed in 

    Perl->Tools->Imenu-POD headers menu entry.  

I see that Imenu still shows the perldoc headers.

So

    cperl-imenu-index-pod is a variable defined in `cperl-mode.el'.
    Its value is t

    Documentation:
    *Whether POD `=head' directives should be indexed by imenu.

the first line of the docstring is misleading.

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Btw, if you are convinced that what this patch does is "the norm" rather
than "an exception", you may as well consider removing the variable.

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