Add "PKCS#11 URIs compliant with RFC7512" patch

[chipitsine]

added patch from OpenSC/pkcs11-helper#4

[mattock]

In yesterday's community meeting @dazo and @cron2 gave a feature-ACK for bundling this patch in new 2.4 Windows installers.

@chipitsine : does the patch actually apply? I'm asking because the old lzo-2.05 patch had this header:

#diff -urNp lzo-2.05/Makefile.am lzo-2.05.1//Makefile.am

This PR's patch has this header:

diff --git a/lib/pkcs11h-serialization.c b/lib/pkcs11h-serialization.c

I think you would need to have this instead:

diff --git a/pkcs11-helper-1.11/lib/pkcs11h-serialization.c b/pkcs11-helper-1.11/lib/pkcs11h-serialization.c

This way openvpn-build would know that it needs to patch pkcs11-helper.

[chipitsine]

@mattock , I tested, patch does apply.

can you please test yourself as well ?

just 'git clone -b RFC7512 https://github.com/chipitsine/openvpn-build' and build it ?

[chipitsine]

@mattock , how was your test ?

I think, as long as we apply patch with "-p1", the header does not matter

[mattock]

@chipitsine : haven't had the time to test yet. That said, I will need to rebuild at least 2.3-based Windows installers late next week. That will be a good time to verify this patch also.

[chipitsine]

@mattock , did you test it?

[mattock]

As agreed in today's IRC meeting I'll merge this now.