scd: PC/SC cleanup

[NIIBE Yutaka]

I applied the patch to both (master and STABLE-BRANCH-2-0).

On 2013-03-21 at 10:47 +0100, Werner Koch wrote:
> >     http://bugs.g10code.com/gnupg/issue1358
> >
> > It's a report for 1.4.11, but talking about same issue.
> 
> Can you please add a remark that this bug has been solved for 2.x.  I
> don't think we should put any work in fixing it for 1.4.

I tried.  But sorry, the issue was not reported by me, thus, I don't
have privilege to add an comment to the issue on the BTS.
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