add OpenSC package

OpenSC is a smart card middleware.
Patches for support of the GnuK USB token have been added.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
add OpenSC's libp11 library

libp11 is a PKCS#11 wrapper library

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
add engine_pkcs11

This adds support for using PKCS#11 modules (such as opensc_pkcs11)
as an OpenSSL engine for RSA.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
openssh: strip openssh-sftp-server dependencies, notably openssl

openssh-sftp-server is actually a tiny binary that has nearly no dependencies:
$ mips-openwrt-linux-objdump -x sftp-server | grep NEEDED
  NEEDED               libgcc_s.so.1
  NEEDED               libc.so.0

Stripping its DEPENDS allows building a system with SFTP support, without
pulling in OpenSSL.
Merge pull request #36 from cpatulea/master

openssh: strip openssh-sftp-server dependencies, notably openssl